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• Inlining an array of non-default constructible objects in a C++ class

  - by porgarmingduod

  C++ doesn't allow a class containing an array of items that are not default constructible: class Gordian { public: int member; Gordian(int must_have_variable) : member(must_have_variable) {} }; class Knot { Gordian* pointer_array[8]; // Sure, this works. Gordian inlined_array[8]; // Won't compile. Can't be initialized. }; As even beginner C++ users know, the language guarantees that all members are initialized when constructing a class. And it doesn't trust the user to initialize everything in the constructor - one has to provide valid arguments to the constructors of all members before the body of the constructor even starts. Generally, that's a great idea as far as I'm concerned, but I've come across a situation where it would be a lot easier if I could actually have an array of non-default constructible objects. The obvious solution: Have an array of pointers to the objects. This is not optimal in my case, as I am using shared memory. It would force me to do extra allocation from an already contended resource (that is, the shared memory). The entire reason I want to have the array inlined in the object is to reduce the number of allocations. This is a situation where I would be willing to use a hack, even an ugly one, provided it works. One possible hack I am thinking about would be: class Knot { public: struct dummy { char padding[sizeof(Gordian)]; }; dummy inlined_array[8]; Gordian* get(int index) { return reinterpret_cast<Gordian*>(&inlined_array[index]); } Knot() { for (int x = 0; x != 8; x++) { new (get(x)) Gordian(x*x); } } }; Sure, it compiles, but I'm not exactly an experienced C++ programmer. That is, I couldn't possibly trust my hacks less. So, the questions: 1) Does the hack I came up with seem workable? What are the issues? (I'm mainly concerned with C++0x on newer versions of GCC). 2) Is there a better way to inline an array of non-default constructible objects in a class?

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• php code is not fetching data from mysql database using wamp server

  - by john

  I want to display a table from database in phpMyAdmin by putting the following conditions that in every different options in drop down menu it displays different table from database by pressing the button of search. But it is not doing so. <p class="h2">Quick Search</p> <div class="sb2_opts"> <p></p> <form method="post" action="" > <p>Enter your source and destination.</p> <p>From:</p> <select name="from"> <option value="Islamabad">Islamabad</option> <option value="Lahore">Lahore</option> <option value="murree">Murree</option> <option value="Muzaffarabad">Muzaffarabad</option> </select> <p>To:</p> <select name="To"> <option value="Islamabad">Islamabad</option> <option value="Lahore">Lahore</option> <option value="murree">Murree</option> <option value="Muzaffarabad">Muzaffarabad</option> </select> <input type="submit" value="search" /> </form> </form> </table> <?php $con=mysqli_connect("localhost","root","","test"); if (mysqli_connect_errno()) { echo "Failed to connect to MySQL: " . mysqli_connect_error(); } if(isset($_POST['from']) and isset($_POST['To'])) { $from = $_POST['from'] ; $to = $_POST['To'] ; $table = array($from, $to); switch ($table) { case array ("Islamabad", "Lahore") : $result = mysqli_query($con,"SELECT * FROM flights"); echo "</flights>"; //table name is flights break; case array ("Islamabad", "Murree") : $result = mysqli_query($con,"SELECT * FROM isb to murree"); echo "</isb to murree>"; //table name isb to murree ; break; case array ("Islamabad", "Muzaffarabad") : $result = mysqli_query($con,"SELECT * FROM isb to muzz"); echo "</isb to muzz>"; break; //..... //...... default: echo "Your choice is nor valid !!"; } } mysqli_close($con); ?>

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• Android: Unable to access a local website over HTTPS

  - by user1253789

  I am trying to access a locally hosted website and get its HTML source to parse. I have few questions: 1) Can I use "https://An IP ADDRESS HERE" as a valid URL to try and access. I do not want to make changes in the /etc/hosts file so I want to do it this way. 2) I cannot get the html, since it is giving me Handshake exceptions and Certificate issues. I have tried a lot of help available over the web , but am not successful. Here is the code I am using: public class MainActivity extends Activity { private TextView textView; String response = ""; String finalresponse=""; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView = (TextView) findViewById(R.id.TextView01); System.setProperty("javax.net.ssl.trustStore","C:\\User\\*" ); System.setProperty("javax.net.ssl.trustStorePassword", "" ); } private class DownloadWebPageTask extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... urls) { TrustManager[] trustAllCerts = new TrustManager[] { new X509TrustManager() { public java.security.cert.X509Certificate[] getAcceptedIssuers() { return null; } public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType) { } public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType) { } } }; try { SSLContext sc = SSLContext.getInstance("SSL"); sc.init(null, trustAllCerts, new java.security.SecureRandom()); HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory()); } catch (Exception e) { } try { URL url = new URL("https://172.27.224.133"); HttpsURLConnection con =(HttpsURLConnection)url.openConnection(); con.setHostnameVerifier(new AllowAllHostnameVerifier()); finalresponse=readStream(con.getInputStream()); } catch (Exception e) { e.printStackTrace(); } return finalresponse; } private String readStream(InputStream in) { BufferedReader reader = null; try { reader = new BufferedReader(new InputStreamReader(in)); String line = ""; while ((line = reader.readLine()) != null) { response+=line; } } catch (IOException e) { e.printStackTrace(); } finally { if (reader != null) { try { reader.close(); } catch (IOException e) { e.printStackTrace(); } } } return response; } @Override protected void onPostExecute(String result) { textView.setText(finalresponse); } } public void readWebpage(View view) { DownloadWebPageTask task = new DownloadWebPageTask(); task.execute(new String[] { "https://172.27.224.133" }); } }

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• How to find same-value rectangular areas of a given size in a matrix most efficiently?

  - by neo

  My problem is very simple but I haven't found an efficient implementation yet. Suppose there is a matrix A like this: 0 0 0 0 0 0 0 4 4 2 2 2 0 0 4 4 2 2 2 0 0 0 0 2 2 2 1 1 0 0 0 0 0 1 1 Now I want to find all starting positions of rectangular areas in this matrix which have a given size. An area is a subset of A where all numbers are the same. Let's say width=2 and height=3. There are 3 areas which have this size: 2 2 2 2 0 0 2 2 2 2 0 0 2 2 2 2 0 0 The result of the function call would be a list of starting positions (x,y starting with 0) of those areas. List((2,1),(3,1),(5,0)) The following is my current implementation. "Areas" are called "surfaces" here. case class Dimension2D(width: Int, height: Int) case class Position2D(x: Int, y: Int) def findFlatSurfaces(matrix: Array[Array[Int]], surfaceSize: Dimension2D): List[Position2D] = { val matrixWidth = matrix.length val matrixHeight = matrix(0).length var resultPositions: List[Position2D] = Nil for (y <- 0 to matrixHeight - surfaceSize.height) { var x = 0 while (x <= matrixWidth - surfaceSize.width) { val topLeft = matrix(x)(y) val topRight = matrix(x + surfaceSize.width - 1)(y) val bottomLeft = matrix(x)(y + surfaceSize.height - 1) val bottomRight = matrix(x + surfaceSize.width - 1)(y + surfaceSize.height - 1) // investigate further if corners are equal if (topLeft == bottomLeft && topLeft == topRight && topLeft == bottomRight) { breakable { for (sx <- x until x + surfaceSize.width; sy <- y until y + surfaceSize.height) { if (matrix(sx)(sy) != topLeft) { x = if (x == sx) sx + 1 else sx break } } // found one! resultPositions ::= Position2D(x, y) x += 1 } } else if (topRight != bottomRight) { // can skip x a bit as there won't be a valid match in current row in this area x += surfaceSize.width } else { x += 1 } } } return resultPositions } I already tried to include some optimizations in it but I am sure that there are far better solutions. Is there a matlab function existing for it which I could port? I'm also wondering whether this problem has its own name as I didn't exactly know what to google for. Thanks for thinking about it! I'm excited to see your proposals or solutions :)

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• Do While loop breaks after incorrect input?

  - by Daminkz

  I am trying to have a loop continue to prompt the user for an option. When I get a string of characters instead of an int, the program loops indefinitely. I have tried setting the variable result to NULL, clearing the input stream, and have enclosed in try{}catch blocks (not in this example). Can anyone explain to me why this is? #include <iostream> #include <vector> #include <string> using namespace std; int menu(string question, vector<string> options) { int result; cout << question << endl; for(int i = 0; i < options.size(); i++) { cout << '[' << i << ']' << options[i] << endl; } bool ans = false; do { cin >> result; cin.ignore(1000, 10); if (result < options.size() ) { ans = true; } else { cout << "You must enter a valid option." << endl; result = NULL; ans = false; } } while(!ans); return result; } int main() { string menuQuestion = "Welcome to my game. What would you like to do?"; vector<string> mainMenu; mainMenu.push_back("Play Game"); mainMenu.push_back("Load Game"); mainMenu.push_back("About"); mainMenu.push_back("Exit"); int result = menu(menuQuestion, mainMenu); cout << "You entered: " << result << endl; return 0; }

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• Detect if class has overloaded function fails on Comeau compiler

  - by Frank

  Hi Everyone, I'm trying to use SFINAE to detect if a class has an overloaded member function that takes a certain type. The code I have seems to work correctly in Visual Studio and GCC, but does not compile using the Comeau online compiler. Here is the code I'm using: #include <stdio.h> //Comeau doesnt' have boost, so define our own enable_if_c template<bool value> struct enable_if_c { typedef void type; }; template<> struct enable_if_c< false > {}; //Class that has the overloaded member function class TestClass { public: void Func(float value) { printf( "%f\n", value ); } void Func(int value) { printf( "%i\n", value ); } }; //Struct to detect if TestClass has an overloaded member function for type T template<typename T> struct HasFunc { template<typename U, void (TestClass::*)( U )> struct SFINAE {}; template<typename U> static char Test(SFINAE<U, &TestClass::Func>*); template<typename U> static int Test(...); static const bool Has = sizeof(Test<T>(0)) == sizeof(char); }; //Use enable_if_c to only allow the function call if TestClass has a valid overload for T template<typename T> typename enable_if_c<HasFunc<T>::Has>::type CallFunc(TestClass &test, T value) { test.Func( value ); } int main() { float value1 = 0.0f; int value2 = 0; TestClass testClass; CallFunc( testClass, value1 ); //Should call TestClass::Func( float ) CallFunc( testClass, value2 ); //Should call TestClass::Func( int ) } The error message is: no instance of function template "CallFunc" matches the argument list. It seems that HasFunc::Has is false for int and float when it should be true. Is this a bug in the Comeau compiler? Am I doing something that's not standard? And if so, what do I need to do to fix it?

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• jQuery reference to (this) does not work?

  - by FFish

  I have this href link with text either "attivo" or "non attivo" User can set the item to 'active' or 'closed' in the database with an ajax request $.post() I have 2 questions for these: I can't get the reference to $(this) to work.. I tried it with a normal link and it works, but not wrapped in if/else?? How can I prevent the user from clicking more than one time on the link and submitting several request? Is this a valid concern? Do I need some sort of a small timer or something? First I was thinking about a javascript confirm message, but that's pretty annoying for this function.. HTML: <dl id='album-list'> <dt id="dt-2">some title</dt> <dd id="dd-2"> some description<br /> <div class='links-right'>status: <a class='toggle-active' href='#'>non attivo</a></div> </dd> </dl> <a class="test" href="#">test</a> JS: $('dd a.toggle-active').click(function() { var a_ref = $(this); var id = a_ref.parent().parent().attr('id').substring(3); if (a_ref.text() == "non attivo") { var new_active = "active"; // for db in english $.post("ajax-aa.php", {album_id:id, album_active:new_active}, function(data) { // alert("success"); a_ref.text("non attivo"); // change href text }); } else { var new_active = "closed"; // for db in english $.post("ajax-aa.php", {album_id:id, album_active:new_active}, function(data) { // alert("success"); a_ref.text("attivo"); // change href text }); } return false; }); $('a.test').click(function() { var a_ref = $(this); $.post("ajax-aa.php", {album_id:2, album_active:"active"}, function(data) { a_ref.text("changed"); }); return false; })

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• best alternative to in-definition initialization of static class members? (for SVN keywords)

  - by Jeff

  I'm storing expanded SVN keyword literals for .cpp files in 'static char const *const' class members and want to store the .h descriptions as similarly as possible. In short, I need to guarantee single instantiation of a static member (presumably in a .cpp file) to an auto-generated non-integer literal living in a potentially shared .h file. Unfortunately the language makes no attempt to resolve multiple instantiations resulting from assignments made outside class definitions and explicitly forbids non-integer inits inside class definitions. My best attempt (using static-wrapping internal classes) is not too dirty, but I'd really like to do better. Does anyone have a way to template the wrapper below or have an altogether superior approach? // Foo.h: class with .h/.cpp SVN info stored and logged statically class Foo { static Logger const verLog; struct hInfoWrap; public: static hInfoWrap const hInfo; static char const *const cInfo; }; // Would like to eliminate this per-class boilerplate. struct Foo::hInfoWrap { hInfoWrapper() : text("$Id$") { } char const *const text; }; ... // Foo.cpp: static inits called here Foo::hInfoWrap const Foo::hInfo; char const *const Foo::cInfo = "$Id$"; Logger const Foo::verLog(Foo::cInfo, Foo::hInfo.text); ... // Helper.h: output on construction, with no subsequent activity or stored fields class Logger { Logger(char const *info1, char const *info2) { cout << info0 << endl << info1 << endl; } }; Is there a way to get around the static linkage address issue for templating the hInfoWrap class on string literals? Extern char pointers assigned outside class definitions are linguistically valid but fail in essentially the same manner as direct member initializations. I get why the language shirks the whole resolution issue, but it'd be very convenient if an inverted extern member qualifier were provided, where the definition code was visible in class definitions to any caller but only actually invoked at the point of a single special declaration elsewhere. Anyway, I digress. What's the best solution for the language we've got, template or otherwise? Thanks!

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• Is it thread safe to read a form controls value (but not change it) without using Invoke/BeginInvoke from another thread

  - by goku_da_master

  I know you can read a gui control from a worker thread without using Invoke/BeginInvoke because my app is doing it now. The cross thread exception error is not being thrown and my System.Timers.Timer thread is able to read gui control values just fine (unlike this guy: can a worker thread read a control in the GUI?) Question 1: Given the cardinal rule of threads, should I be using Invoke/BeginInvoke to read form control values? And does this make it more thread-safe? The background to this question stems from a problem my app is having. It seems to randomly corrupt form controls another thread is referencing. (see question 2) Question 2: I have a second thread that needs to update form control values so I Invoke/BeginInvoke to update those values. Well this same thread needs a reference to those controls so it can update them. It holds a list of these controls (say DataGridViewRow objects). Sometimes (not always), the DataGridViewRow reference gets "corrupt". What I mean by corrupt, is the reference is still valid, but some of the DataGridViewRow properties are null (ex: row.Cells). Is this caused by question 1 or can you give me any tips on why this might be happening? Here's some code (the last line has the problem): public partial class MyForm : Form { void Timer_Elapsed(object sender) { // we're on a new thread (this function gets called every few seconds) UpdateUiHelper updateUiHelper = new UpdateUiHelper(this); foreach (DataGridViewRow row in dataGridView1.Rows) { object[] values = GetValuesFromDb(); updateUiHelper.UpdateRowValues(row, values[0]); } // .. do other work here updateUiHelper.UpdateUi(); } } public class UpdateUiHelper { private readonly Form _form; private Dictionary<DataGridViewRow, object> _rows; private delegate void RowDelegate(DataGridViewRow row); private readonly object _lockObject = new object(); public UpdateUiHelper(Form form) { _form = form; _rows = new Dictionary<DataGridViewRow, object>(); } public void UpdateRowValues(DataGridViewRow row, object value) { if (_rows.ContainsKey(row)) _rows[row] = value; else { lock (_lockObject) { _rows.Add(row, value); } } } public void UpdateUi() { foreach (DataGridViewRow row in _rows.Keys) { SetRowValueThreadSafe(row); } } private void SetRowValueThreadSafe(DataGridViewRow row) { if (_form.InvokeRequired) { _form.Invoke(new RowDelegate(SetRowValueThreadSafe), new object[] { row }); return; } // now we're on the UI thread object newValue = _rows[row]; row.Cells[0].Value = newValue; // randomly errors here with NullReferenceException, but row is never null! }

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• login not working when changing from mysql to mysqli

  - by user1438647

  I have a code below where it logs a teacher in by matching it's username and password in the database, if correct, then log in, if incorrect, then display a message. <?php session_start(); $username="xxx"; $password="xxx"; $database="mobile_app"; $link = mysqli_connect('localhost',$username,$password); mysqli_select_db($link, $database) or die( "Unable to select database"); foreach (array('teacherusername','teacherpassword') as $varname) { $$varname = (isset($_POST[$varname])) ? $_POST[$varname] : ''; } ?> <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post" id="teachLoginForm"> <p>Username</p><p><input type="text" name="teacherusername" /></p> <!-- Enter Teacher Username--> <p>Password</p><p><input type="password" name="teacherpassword" /></p> <!-- Enter Teacher Password--> <p><input id="loginSubmit" type="submit" value="Login" name="submit" /></p> </form> <?php if (isset($_POST['submit'])) { $query = " SELECT * FROM Teacher t WHERE (t.TeacherUsername = '".mysqli_real_escape_string($teacherusername)."') AND (t.TeacherPassword = '".mysqli_real_escape_string($teacherpassword)."') "; $result = mysqli_query($link, $query); $num = mysqli_num_rows($result); $loged = false; while($row = mysqli_fetch_array($result)) { if ($_POST['teacherusername'] == ($row['TeacherUsername']) && $_POST['teacherpassword'] == ($row['TeacherPassword'])) { $loged = true; } $_SESSION['teacherforename'] = $row['TeacherForename']; $_SESSION['teachersurname'] = $row['TeacherSurname']; $_SESSION['teacherusername'] = $row['TeacherUsername']; } if ($loged == true){ header( 'Location: menu.php' ) ; }else{ echo "The Username or Password that you Entered is not Valid. Try Entering it Again."; } mysqli_close($link); } ?> Now the problem is that even if the teacher has entered in the correct username and password, it still doesn't let the teacher log in. When the code above was the old mysql() code, it worked fine as teacher was able to login when username and password match, but when trying to change the code into mysqli then it causes login to not work even though username and password match. What am I doing wrong?

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• Issue in event.PreventDefault()

  - by Prathiba

  I'm using twitter bootstrap in my application. i gave e.preventDefault for link button in $(document).reday(), but it is not working. Here is my code: Master page: <a id="lnkLogout" href="javascript:void(0);" onclick="PageLogout();"><i class="icon-off"> </i>Logout</a> <script type="text/javascript" language="javascript"> $(document).ready(function () { $('#lnkLogout').click(function (e) { e.preventDefault(); }); }); function PageLogout() { //Code for logout from the application.... } </script> SampleDefaultPage.aspx : <div class="row-fluid"> <div class="form-horizontal"> <h4 class="header blue bolder smaller"> Contact</h4> <div class="control-group"> <label for="form-field-email" class="control-label"> Email</label> <div class="controls"> <input type="text" style="width:200px;" data-val="true" data-val-required="Mobile Number is required." id="txtEmail"> <div class="space-3"> </div> <span data-valmsg-replace="true" data-valmsg-for="txtEmail" class="field-validation-valid text-warning red"></span> </div> </div> <div class="control-group"> <label for="form-field-website" class="control-label"> Phone Number</label> <div class="controls"> <input type="text" style="width:200px;" id="txtPhno"> </div> </div> </div> I have given txtEmail as mandatory field. if i left that field blank and click on Logout button in Master page, it says txtEmail is required. i dint do any validation in Logout onclick event. I have given preventDefault for Logout link. But still facing an issue. I should be able to logout even though txtEmail is left blank. Thank you all in advance for your response.

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• Styling related issue in IE8

  - by Ajith

  I am using a background image to display as a button. The button shows up well in all versions of firefox, chrome, opera etc. However, the image fails to render itself in IE8. Only the image is not being shown, some of the other class styling gets applied such as width, height etc. Even more confounding is that in another page(though a different class and style sheet), an image of similar proportions gets displayed in similar usage. The image format is JPG. I'm copy-pasting the valid style attributes for both cases as shown by firebug below. None of the below buttons are displayed. button classes are applied as class="cart-button login", class="cart-button update", class="cart-button checkout" and class="cart-button continue" and are inside some divs. .cart-button{ height: 28px; cursor: pointer; border: none; float: left; } .cart-button:hover{ background-position: 0 -28px; } .login{ width: 58px; background:url(/../../templates/animalcare/i/login.jpg)no-repeat; margin:0 0 20px 0; clear: both; } .update{ width: 63px; background:url(/../../templates/animalcare/i/update.jpg)no-repeat; margin:0 0 20px 15px; float: left; } .checkout{ width: 77px; background:url(/../../templates/animalcare/i/checkout.jpg)no-repeat; float:right; margin:0 25px 30px 10px; } .continue{ width: 132px; background:url(/../../templates/animalcare/i/continue.jpg)no-repeat; float:right; margin:0 0 30px 0px; } The below is the only image button that gets displayed. It is located inside a table. It is in a different style sheet - hence the path difference. .add-to-cart{ width:102px; height:28px; float:left; background:url(i/add_to_cart.jpg) no-repeat; cursor:pointer; border:none; margin:10px 0 5px 0; } .add-to-cart:hover{ background-position:0 -28px; }

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• How to detect invalid image URL with JAVA?

  - by Cataclysm

  I have a method to download image from URL. As like below.. public static byte[] downloadImageFromURL(final String strUrl) { InputStream in; ByteArrayOutputStream out = new ByteArrayOutputStream(); try { URL url = new URL(strUrl); in = new BufferedInputStream(url.openStream()); byte[] buf = new byte[2048]; int n = 0; while (-1 != (n = in.read(buf))) { out.write(buf, 0, n); } out.close(); in.close(); } catch (IOException e) { return null; } return out.toByteArray(); } I have an image url and it is valid. for example. https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcTxfYM-hnD-Z80tgWdIgQKchKe-MXVUfTpCw1R5KkfJlbRbgr3Zcg My problem is I don't want to download if image is really not exists.Like .... https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcTxfYM-hnD-Z80tgWdIgQKchKe-MXVUfTpCw1R5KkfJlbRbgr3Zcgaaaaabbbbdddddddddddddddddddddddddddd This image shouldn't be download by my method. So , how can I know the giving image URL is not really exists. I don't want to validate my URL (I think that may not my solution ). So, I googled for that. From this article ... How to check if a URL exists or returns 404 with Java? and Java check if file exists on remote server using its url But this con.getResponseCode() will always return status code "200". This mean my method will also download invalid image urls. So , I output my bufferStream as like... System.out.println(in.read(buf)); Invalid image URL produces "43". So , I add these lines of codes in my method. if (in.read(buf) == 43) { return null; } It is ok. But I don't think that will always satisfy. Has another way to get it ? am I right? I would really appreciate any suggestions. This problem may struct my head. Thanks for reading my question.

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• Enabling Kerberos Authentication for Reporting Services

  - by robcarrol

  Recently, I’ve helped several customers with Kerberos authentication problems with Reporting Services and Analysis Services, so I’ve decided to write this blog post and pull together some useful resources in one place (there are 2 whitepapers in particular that I found invaluable configuring Kerberos authentication, and these can be found in the references section at the bottom of this post). In most of these cases, the problem has manifested itself with the Login failed for User ‘NT Authority\Anonymous’ (“double-hop”) error. By default, Reporting Services uses Windows Integrated Authentication, which includes the Kerberos and NTLM protocols for network authentication. Additionally, Windows Integrated Authentication includes the negotiate security header, which prompts the client to select Kerberos or NTLM for authentication. The client can access reports which have the appropriate permissions by using Kerberos for authentication. Servers that use Kerberos authentication can impersonate those clients and use their security context to access network resources. You can configure Reporting Services to use both Kerberos and NTLM authentication; however this may lead to a failure to authenticate. With negotiate, if Kerberos cannot be used, the authentication method will default to NTLM. When negotiate is enabled, the Kerberos protocol is always used except when: Clients/servers that are involved in the authentication process cannot use Kerberos. The client does not provide the information necessary to use Kerberos. An in-depth discussion of Kerberos authentication is beyond the scope of this post, however when users execute reports that are configured to use Windows Integrated Authentication, their logon credentials are passed from the report server to the server hosting the data source. Delegation needs to be set on the report server and Service Principle Names (SPNs) set for the relevant services. When a user processes a report, the request must go through a Web server on its way to a database server for processing. Kerberos authentication enables the Web server to request a service ticket from the domain controller; impersonate the client when passing the request to the database server; and then restrict the request based on the user’s permissions. Each time a server is required to pass the request to another server, the same process must be used. Kerberos authentication is supported in both native and SharePoint integrated mode, but I’ll focus on native mode for the purpose of this post (I’ll explain configuring SharePoint integrated mode and Kerberos authentication in a future post). Configuring Kerberos avoids the authentication failures due to double-hop issues. These double-hop errors occur when a users windows domain credentials can’t be passed to another server to complete the user’s request. In the case of my customers, users were executing Reporting Services reports that were configured to query Analysis Services cubes on a separate machine using Windows Integrated security. The double-hop issue occurs as NTLM credentials are valid for only one network hop, subsequent hops result in anonymous authentication. The client attempts to connect to the report server by making a request from a browser (or some other application), and the connection process begins with authentication. With NTLM authentication, client credentials are presented to Computer 2. However Computer 2 can’t use the same credentials to access Computer 3 (so we get the Anonymous login error). To access Computer 3 it is necessary to configure the connection string with stored credentials, which is what a number of customers I have worked with have done to workaround the double-hop authentication error. However, to get the benefits of Windows Integrated security, a better solution is to enable Kerberos authentication. Again, the connection process begins with authentication. With Kerberos authentication, the client and the server must demonstrate to one another that they are genuine, at which point authentication is successful and a secure client/server session is established. In the illustration above, the tiers represent the following: Client tier (computer 1): The client computer from which an application makes a request. Middle tier (computer 2): The Web server or farm where the client’s request is directed. Both the SharePoint and Reporting Services server(s) comprise the middle tier (but we’re only concentrating on native deployments just now). Back end tier (computer 3): The Database/Analysis Services server/Cluster where the requested data is stored. In order to enable Kerberos authentication for Reporting Services it’s necessary to configure the relevant SPNs, configure trust for delegation for server accounts, configure Kerberos with full delegation and configure the authentication types for Reporting Services. Service Principle Names (SPNs) are unique identifiers for services and identify the account’s type of service. If an SPN is not configured for a service, a client account will be unable to authenticate to the servers using Kerberos. You need to be a domain administrator to add an SPN, which can be added using the SetSPN utility. For Reporting Services in native mode, the following SPNs need to be registered --SQL Server Service SETSPN -S mssqlsvc/servername:1433 Domain\SQL For named instances, or if the default instance is running under a different port, then the specific port number should be used. --Reporting Services Service SETSPN -S http/servername Domain\SSRS SETSPN -S http/servername.domain.com Domain\SSRS The SPN should be set for the NETBIOS name of the server and the FQDN. If you access the reports using a host header or DNS alias, then that should also be registered SETSPN -S http/www.reports.com Domain\SSRS --Analysis Services Service SETSPN -S msolapsvc.3/servername Domain\SSAS Next, you need to configure trust for delegation, which refers to enabling a computer to impersonate an authenticated user to services on another computer: Location Description Client 1. The requesting application must support the Kerberos authentication protocol. 2. The user account making the request must be configured on the domain controller. Confirm that the following option is not selected: Account is sensitive and cannot be delegated. Servers 1. The service accounts must be trusted for delegation on the domain controller. 2. The service accounts must have SPNs registered on the domain controller. If the service account is a domain user account, the domain administrator must register the SPNs. In Active Directory Users and Computers, verify that the domain user accounts used to access reports have been configured for delegation (the ‘Account is sensitive and cannot be delegated’ option should not be selected): We then need to configure the Reporting Services service account and computer to use Kerberos with full delegation:   We also need to do the same for the SQL Server or Analysis Services service accounts and computers (depending on what type of data source you are connecting to in your reports). Finally, and this is the part that sometimes gets over-looked, we need to configure the authentication type correctly for reporting services to use Kerberos authentication. This is configured in the Authentication section of the RSReportServer.config file on the report server. <Authentication> <AuthenticationTypes>           <RSWindowsNegotiate/> </AuthenticationTypes> <EnableAuthPersistence>true</EnableAuthPersistence> </Authentication> This will enable Kerberos authentication for Internet Explorer. For other browsers, see the link below. The report server instance must be restarted for these changes to take effect. Once these changes have been made, all that’s left to do is test to make sure Kerberos authentication is working properly by running a report from report manager that is configured to use Windows Integrated authentication (either connecting to Analysis Services or SQL Server back-end). Resources: Manage Kerberos Authentication Issues in a Reporting Services Environment http://download.microsoft.com/download/B/E/1/BE1AABB3-6ED8-4C3C-AF91-448AB733B1AF/SSRSKerberos.docx Configuring Kerberos Authentication for Microsoft SharePoint 2010 Products http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=23176 How to: Configure Windows Authentication in Reporting Services http://msdn.microsoft.com/en-us/library/cc281253.aspx RSReportServer Configuration File http://msdn.microsoft.com/en-us/library/ms157273.aspx#Authentication Planning for Browser Support http://msdn.microsoft.com/en-us/library/ms156511.aspx

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• Parallelism in .NET – Part 15, Making Tasks Run: The TaskScheduler

  - by Reed

  In my introduction to the Task class, I specifically made mention that the Task class does not directly provide it’s own execution.  In addition, I made a strong point that the Task class itself is not directly related to threads or multithreading.  Rather, the Task class is used to implement our decomposition of tasks.  Once we’ve implemented our tasks, we need to execute them.  In the Task Parallel Library, the execution of Tasks is handled via an instance of the TaskScheduler class. The TaskScheduler class is an abstract class which provides a single function: it schedules the tasks and executes them within an appropriate context.  This class is the class which actually runs individual Task instances.  The .NET Framework provides two (internal) implementations of the TaskScheduler class. Since a Task, based on our decomposition, should be a self-contained piece of code, parallel execution makes sense when executing tasks.  The default implementation of the TaskScheduler class, and the one most often used, is based on the ThreadPool.  This can be retrieved via the TaskScheduler.Default property, and is, by default, what is used when we just start a Task instance with Task.Start(). Normally, when a Task is started by the default TaskScheduler, the task will be treated as a single work item, and run on a ThreadPool thread.  This pools tasks, and provides Task instances all of the advantages of the ThreadPool, including thread pooling for reduced resource usage, and an upper cap on the number of work items.  In addition, .NET 4 brings us a much improved thread pool, providing work stealing and reduced locking within the thread pool queues.  By using the default TaskScheduler, our Tasks are run asynchronously on the ThreadPool. There is one notable exception to my above statements when using the default TaskScheduler.  If a Task is created with the TaskCreationOptions set to TaskCreationOptions.LongRunning, the default TaskScheduler will generate a new thread for that Task, at least in the current implementation.  This is useful for Tasks which will persist for most of the lifetime of your application, since it prevents your Task from starving the ThreadPool of one of it’s work threads. The Task Parallel Library provides one other implementation of the TaskScheduler class.  In addition to providing a way to schedule tasks on the ThreadPool, the framework allows you to create a TaskScheduler which works within a specified SynchronizationContext.  This scheduler can be retrieved within a thread that provides a valid SynchronizationContext by calling the TaskScheduler.FromCurrentSynchronizationContext() method. This implementation of TaskScheduler is intended for use with user interface development.  Windows Forms and Windows Presentation Foundation both require any access to user interface controls to occur on the same thread that created the control.  For example, if you want to set the text within a Windows Forms TextBox, and you’re working on a background thread, that UI call must be marshaled back onto the UI thread.  The most common way this is handled depends on the framework being used.  In Windows Forms, Control.Invoke or Control.BeginInvoke is most often used.  In WPF, the equivelent calls are Dispatcher.Invoke or Dispatcher.BeginInvoke. As an example, say we’re working on a background thread, and we want to update a TextBlock in our user interface with a status label.  The code would typically look something like: // Within background thread work... string status = GetUpdatedStatus(); Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action( () => { statusLabel.Text = status; })); // Continue on in background method .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This works fine, but forces your method to take a dependency on WPF or Windows Forms.  There is an alternative option, however.  Both Windows Forms and WPF, when initialized, setup a SynchronizationContext in their thread, which is available on the UI thread via the SynchronizationContext.Current property.  This context is used by classes such as BackgroundWorker to marshal calls back onto the UI thread in a framework-agnostic manner. The Task Parallel Library provides the same functionality via the TaskScheduler.FromCurrentSynchronizationContext() method.  When setting up our Tasks, as long as we’re working on the UI thread, we can construct a TaskScheduler via: TaskScheduler uiScheduler = TaskScheduler.FromCurrentSynchronizationContext(); We then can use this scheduler on any thread to marshal data back onto the UI thread.  For example, our code above can then be rewritten as: string status = GetUpdatedStatus(); (new Task(() => { statusLabel.Text = status; })) .Start(uiScheduler); // Continue on in background method This is nice since it allows us to write code that isn’t tied to Windows Forms or WPF, but is still fully functional with those technologies.  I’ll discuss even more uses for the SynchronizationContext based TaskScheduler when I demonstrate task continuations, but even without continuations, this is a very useful construct. In addition to the two implementations provided by the Task Parallel Library, it is possible to implement your own TaskScheduler.  The ParallelExtensionsExtras project within the Samples for Parallel Programming provides nine sample TaskScheduler implementations.  These include schedulers which restrict the maximum number of concurrent tasks, run tasks on a single threaded apartment thread, use a new thread per task, and more.

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• Creating packages in code - Package Configurations

  Continuing my theme of building various types of packages in code, this example shows how to building a package with package configurations. Incidentally it shows you how to add a variable, and a connection too. It covers the five most common configurations: Configuration File Indirect Configuration File SQL Server Indirect SQL Server Environment Variable  For a general overview try the SQL Server Books Online Package Configurations topic. The sample uses a a simple helper function ApplyConfig to create or update a configuration, although in the example we will only ever create. The most useful knowledge is the configuration string (Configuration.ConfigurationString) that you need to set. Configuration Type Configuration String Description Configuration File The full path and file name of an XML configuration file. The file can contain one or more configuration and includes the target path and new value to set. Indirect Configuration File An environment variable the value of which contains full path and file name of an XML configuration file as per the Configuration File type described above. SQL Server A three part configuration string, with each part being quote delimited and separated by a semi-colon. -- The first part is the connection manager name. The connection tells you which server and database to look for the configuration table. -- The second part is the name of the configuration table. The table is of a standard format, use the Package Configuration Wizard to help create an example, or see the sample script files below. The table contains one or more rows or configuration items each with a target path and new value. -- The third and final part is the optional filter name. A configuration table can contain multiple configurations, and the filter is  literal value that can be used to group items together and act as a filter clause when configurations are being read. If you do not need a filter, just leave the value empty. Indirect SQL Server An environment variable the value of which is the three part configuration string as per the SQL Server type described above. Environment Variable An environment variable the value of which is the value to set in the package. This is slightly different to the other examples as the configuration definition in the package also includes the target information. In our ApplyConfig function this is the only example that actually supplies a target value for the Configuration.PackagePath property. The path is an XPath style path for the target property, \Package.Variables[User::Variable].Properties[Value], the equivalent of which can be seen in the screenshot below, with the object being our variable called Variable, and the property to set is the Value property of that variable object. The configurations as seen when opening the generated package in BIDS: The sample code creates the package, adds a variable and connection manager, enables configurations, and then adds our example configurations. The package is then saved to disk, useful for checking the package and testing, before finally executing, just to prove it is valid. There are some external resources used here, namely some environment variables and a table, see below for more details. namespace Konesans.Dts.Samples { using System; using Microsoft.SqlServer.Dts.Runtime; public class PackageConfigurations { public void CreatePackage() { // Create a new package Package package = new Package(); package.Name = "ConfigurationSample"; // Add a variable, the target for our configurations package.Variables.Add("Variable", false, "User", 0); // Add a connection, for SQL configurations // Add the SQL OLE-DB connection ConnectionManager connectionManagerOleDb = package.Connections.Add("OLEDB"); connectionManagerOleDb.Name = "SQLConnection"; connectionManagerOleDb.ConnectionString = "Provider=SQLOLEDB.1;Data Source=(local);Initial Catalog=master;Integrated Security=SSPI;"; // Add our example configurations, first must enable package setting package.EnableConfigurations = true; // Direct configuration file, see sample file this.ApplyConfig(package, "Configuration File", DTSConfigurationType.ConfigFile, "C:\\Temp\\XmlConfig.dtsConfig", string.Empty); // Indirect configuration file, the emvironment variable XmlConfigFileEnvironmentVariable // contains the path to the configuration file, e.g. C:\Temp\XmlConfig.dtsConfig this.ApplyConfig(package, "Indirect Configuration File", DTSConfigurationType.IConfigFile, "XmlConfigFileEnvironmentVariable", string.Empty); // Direct SQL Server configuration, uses the SQLConnection package connection to read // configurations from the [dbo].[SSIS Configurations] table, with a filter of "SampleFilter" this.ApplyConfig(package, "SQL Server", DTSConfigurationType.SqlServer, "\"SQLConnection\";\"[dbo].[SSIS Configurations]\";\"SampleFilter\";", string.Empty); // Indirect SQL Server configuration, the environment variable "SQLServerEnvironmentVariable" // contains the configuration string e.g. "SQLConnection";"[dbo].[SSIS Configurations]";"SampleFilter"; this.ApplyConfig(package, "Indirect SQL Server", DTSConfigurationType.ISqlServer, "SQLServerEnvironmentVariable", string.Empty); // Direct environment variable, the value of the EnvironmentVariable environment variable is // applied to the target property, the value of the "User::Variable" package variable this.ApplyConfig(package, "EnvironmentVariable", DTSConfigurationType.EnvVariable, "EnvironmentVariable", "\\Package.Variables[User::Variable].Properties[Value]"); #if DEBUG // Save package to disk, DEBUG only new Application().SaveToXml(String.Format(@"C:\Temp\{0}.dtsx", package.Name), package, null); Console.WriteLine(@"C:\Temp\{0}.dtsx", package.Name); #endif // Execute package package.Execute(); // Basic check for warnings foreach (DtsWarning warning in package.Warnings) { Console.WriteLine("WarningCode : {0}", warning.WarningCode); Console.WriteLine(" SubComponent : {0}", warning.SubComponent); Console.WriteLine(" Description : {0}", warning.Description); Console.WriteLine(); } // Basic check for errors foreach (DtsError error in package.Errors) { Console.WriteLine("ErrorCode : {0}", error.ErrorCode); Console.WriteLine(" SubComponent : {0}", error.SubComponent); Console.WriteLine(" Description : {0}", error.Description); Console.WriteLine(); } package.Dispose(); } /// <summary> /// Add or update an package configuration. /// </summary> /// <param name="package">The package.</param> /// <param name="name">The configuration name.</param> /// <param name="type">The type of configuration</param> /// <param name="setting">The configuration setting.</param> /// <param name="target">The target of the configuration, leave blank if not required.</param> internal void ApplyConfig(Package package, string name, DTSConfigurationType type, string setting, string target) { Configurations configurations = package.Configurations; Configuration configuration; if (configurations.Contains(name)) { configuration = configurations[name]; } else { configuration = configurations.Add(); } configuration.Name = name; configuration.ConfigurationType = type; configuration.ConfigurationString = setting; configuration.PackagePath = target; } } } The following table lists the environment variables required for the full example to work along with some sample values. Variable Sample value EnvironmentVariable 1 SQLServerEnvironmentVariable "SQLConnection";"[dbo].[SSIS Configurations]";"SampleFilter"; XmlConfigFileEnvironmentVariable C:\Temp\XmlConfig.dtsConfig Sample code, package and configuration file. ConfigurationApplication.cs ConfigurationSample.dtsx XmlConfig.dtsConfig

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• Install Ubuntu Netbook Edition with Wubi Installer

  - by Matthew Guay

  Ubuntu is one of the most popular versions of Linux, and their Netbook Remix edition is especially attractive for netbook owners.  Here we’ll look at how you can easily try out Ubuntu on your netbook without a CD/DVD drive. Netbooks, along with the growing number of thin, full powered laptops, lack a CD/DVD drive.  Installing software isn’t much of a problem since most programs, whether free or for-pay, are available for download.  Operating systems, however, are usually installed from a disk.  You can easily install Windows 7 from a flash drive with our tutorial, but installing Ubuntu from a USB flash drive is more complicated.  However, using Wubi, a Windows installer for Ubuntu, you can easily install it directly on your netbook and even uninstall it with only a few clicks. Getting Started Download and run the Wubi installer for Ubuntu (link below).  In the installer, select the drive you where you wish to install Ubuntu, the size of the installation (this is the amount dedicated to Ubuntu; under 20Gb should be fine), language, username, and desired password.  Also, from the Desktop environment menu, select Ubuntu Netbook to install the netbook edition.  Click Install when your settings are correct. Wubi will automatically download the selected version of Ubuntu and install it on your computer. Windows Firewall may ask if you want to unblock Wubi; select your network and click Allow access. The download will take around an hour on broadband, depending on your internet connection speed.  Once the download is completed, it will automatically install to your computer.  If you’d prefer to have everything downloaded before you start the install, download the ISO of Ubuntu Netbook edition (link below) and save it in the same folder as Wubi. Then, when you run Wubi, select the netbook edition as before and click Install.  Wubi will verify that your download is valid, and will then proceed to install from the downloaded ISO.  This install will only take about 10 minutes. Once the install is finished you will be asked to reboot your computer.  Save anything else you’re working on, and then reboot to finish setting up Ubuntu on your netbook. When your computer reboots, select Ubuntu at the boot screen.  Wubi leaves the default OS as Windows 7, so if you don’t select anything it will boot into Windows 7 after a few seconds. Ubuntu will automatically finish the install when you boot into it the first time.  This took about 12 minutes in our test. When the setup is finished, your netbook will reboot one more time.  Remember again to select Ubuntu at the boot screen.  You’ll then see a second boot screen; press your Enter key to select the default.   Ubuntu only took less than a minute to boot in our test.  When you see the login screen, select your name and enter your password you setup in Wubi.  Now you’re ready to start exploring Ubuntu Netbook Remix. Using Ubuntu Netbook Remix Ubuntu Netbook Remix offers a simple, full-screen interface to take the best advantage of netbooks’ small screens.  Pre-installed applications are displayed in the application launcher, and are organized by category.  Click once to open an application. The first screen on the application launcher shows your favorite programs.  If you’d like to add another application to the favorites pane, click the plus sign beside its icon. Your files from Windows are still accessible from Ubuntu Netbook Remix.  From the home screen, select Files & Folders on the left menu, and then click the icon that says something like 100GB Filesystem under the Volumes section. Now you’ll be able to see all of your files from Windows.  Your user files such as documents, music, and pictures should be located in Documents and Settings in a folder with your user name. You can also easily install a variety of free applications via the Software Installer. Connecting to the internet is also easy, as Ubuntu Netbook Remix automatically recognized the WiFi adaptor on our test netbook, a Samsung N150.  To connect to a wireless network, click the wireless icon on the top right of the screen and select the network’s name from the list. And, if you’d like to customize your screen, right-click on the application launcher and select Change desktop background. Choose a background picture you’d like. Now you’ll see it through your application launcher.  Nice! Most applications are opened full-screen.  You can close them by clicking the x on the right of the program’s name. You can also switch to other applications from their icons on the top left.  Open the home screen by clicking the Ubuntu logo in the far left. Changing Boot Options By default, Wubi will leave Windows as the default operating system, and will give you 10 seconds at boot to choose to boot into Ubuntu.  To change this, boot into Windows and enter Advanced system settings in your start menu search. In this dialog, click Settings under Startup and Recovery. From this dialog, you can select the default operating system and the time to display list of operating systems.  You can enter a lower number to make the boot screen appear for less time. And if you’d rather make Ubuntu the default operating system, select it from the drop-down list.   Uninstalling Ubuntu Netbook Remix If you decide you don’t want to keep Ubuntu Netbook Remix on your computer, you can uninstall it just like you uninstall any normal application.  Boot your computer into Windows, open Control Panel, click Uninstall a Program, and enter ubuntu in the search box.  Select it, and click Uninstall. Click Uninstall at the prompt.  Ubuntu uninstalls very quickly, and removes the entry from the bootloader as well, so your computer is just like it was before you installed it.   Conclusion Ubuntu Netbook Remix offers an attractive Linux interface for netbooks.  We enjoyed trying it out, and found it much more user-friendly than most Linux distros.  And with the Wubi installer, you can install it risk-free and try it out on your netbook.  Or, if you’d like to try out another alternate netbook operating system, check out our article on Jolicloud, another new OS for netbooks. Links Download Wubi Installer for Windows Download Ubuntu Netbook Edition Similar Articles Productive Geek Tips Easily Install Ubuntu Linux with Windows Using the Wubi InstallerInstall VMware Tools on Ubuntu Edgy EftHow to install Spotify in Ubuntu 9.10 using WineInstalling PHP5 and Apache on UbuntuInstalling PHP4 and Apache on Ubuntu TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Explorer++ is a Worthy Windows Explorer Alternative Error Goblin Explains Windows Error Codes Twelve must-have Google Chrome plugins Cool Looking Skins for Windows Media Player 12 Move the Mouse Pointer With Your Face Movement Using eViacam Boot Windows Faster With Boot Performance Diagnostics

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• Validation in Silverlight

  - by Timmy Kokke

  Getting started with the basics Validation in Silverlight can get very complex pretty easy. The DataGrid control is the only control that does data validation automatically, but often you want to validate your own entry form. Values a user may enter in this form can be restricted by the customer and have to fit an exact fit to a list of requirements or you just want to prevent problems when saving the data to the database. Showing a message to the user when a value is entered is pretty straight forward as I’ll show you in the following example.     This (default) Silverlight textbox is data-bound to a simple data class. It has to be bound in “Two-way” mode to be sure the source value is updated when the target value changes. The INotifyPropertyChanged interface must be implemented by the data class to get the notification system to work. When the property changes a simple check is performed and when it doesn’t match some criteria an ValidationException is thrown. The ValidatesOnExceptions binding attribute is set to True to tell the textbox it should handle the thrown ValidationException. Let’s have a look at some code now. The xaml should contain something like below. The most important part is inside the binding. In this case the Text property is bound to the “Name” property in TwoWay mode. It is also told to validate on exceptions. This property is false by default.   <StackPanel Orientation="Horizontal"> <TextBox Width="150" x:Name="Name" Text="{Binding Path=Name, Mode=TwoWay, ValidatesOnExceptions=True}"/> <TextBlock Text="Name"/> </StackPanel>   The data class in this first example is a very simplified person class with only one property: string Name. The INotifyPropertyChanged interface is implemented and the PropertyChanged event is fired when the Name property changes. When the property changes a check is performed to see if the new string is null or empty. If this is the case a ValidationException is thrown explaining that the entered value is invalid.   public class PersonData:INotifyPropertyChanged { private string _name; public string Name { get { return _name; } set { if (_name != value) { if(string.IsNullOrEmpty(value)) throw new ValidationException("Name is required"); _name = value; if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Name")); } } } public event PropertyChangedEventHandler PropertyChanged=delegate { }; } The last thing that has to be done is letting binding an instance of the PersonData class to the DataContext of the control. This is done in the code behind file. public partial class Demo1 : UserControl { public Demo1() { InitializeComponent(); this.DataContext = new PersonData() {Name = "Johnny Walker"}; } }   Error Summary In many cases you would have more than one entry control. A summary of errors would be nice in such case. With a few changes to the xaml an error summary, like below, can be added.           First, add a namespace to the xaml so the control can be used. Add the following line to the header of the .xaml file. xmlns:Controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data.Input"   Next, add the control to the layout. To get the result as in the image showed earlier, add the control right above the StackPanel from the first example. It’s got a small margin to separate it from the textbox a little.   <Controls:ValidationSummary Margin="8"/>   The ValidationSummary control has to be notified that an ValidationException occurred. This can be done with a small change to the xaml too. Add the NotifyOnValidationError to the binding expression. By default this value is set to false, so nothing would be notified. Set the property to true to get it to work.   <TextBox Width="150" x:Name="Name" Text="{Binding Name, Mode=TwoWay, ValidatesOnExceptions=True, NotifyOnValidationError=True}"/>   Data annotation Validating data in the setter is one option, but not my personal favorite. It’s the easiest way if you have a single required value you want to check, but often you want to validate more. Besides, I don’t consider it best practice to write logic in setters. The way used by frameworks like WCF Ria Services is the use of attributes on the properties. Instead of throwing exceptions you have to call the static method ValidateProperty on the Validator class. This call stays always the same for a particular property, not even when you change the attributes on the property. To mark a property “Required” you can use the RequiredAttribute. This is what the Name property is going to look like:   [Required] public string Name { get { return _name; } set { if (_name != value) { Validator.ValidateProperty(value, new ValidationContext(this, null, null){ MemberName = "Name" }); _name = value; if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Name")); } } }   The ValidateProperty method takes the new value for the property and an instance of ValidationContext. The properties passed to the constructor of the ValidationContextclass are very straight forward. This part is the same every time. The only thing that changes is the MemberName property of the ValidationContext. Property has to hold the name of the property you want to validate. It’s the same value you provide the PropertyChangedEventArgs with. The System.ComponentModel.DataAnnotation contains eight different validation attributes including a base class to create your own. They are: RequiredAttribute Specifies that a value must be provided. RangeAttribute The provide value must fall in the specified range. RegularExpressionAttribute Validates is the value matches the regular expression. StringLengthAttribute Checks if the number of characters in a string falls between a minimum and maximum amount. CustomValidationAttribute Use a custom method to validate the value. DataTypeAttribute Specify a data type using an enum or a custom data type. EnumDataTypeAttribute Makes sure the value is found in a enum. ValidationAttribute A base class for custom validation attributes All of these will ensure that an validation exception is thrown, except the DataTypeAttribute. This attribute is used to provide some additional information about the property. You can use this information in your own code.   [Required] [Range(0,125,ErrorMessage = "Value is not a valid age")] public int Age {   It’s no problem to stack different validation attributes together. For example, when an Age is required and must fall in the range from 0 to 125:   [Required, StringLength(255,MinimumLength = 3)] public string Name {   Or in one row like this, for a required Name with at least 3 characters and a maximum of 255:   Delayed validation Having properties marked as required can be very useful. The only downside to the technique described earlier is that you have to change the value in order to get it validated. What if you start out with empty an empty entry form? All fields are empty and thus won’t be validated. With this small trick you can validate at the moment the user click the submit button.   <TextBox Width="150" x:Name="NameField" Text="{Binding Name, Mode=TwoWay, ValidatesOnExceptions=True, NotifyOnValidationError=True, UpdateSourceTrigger=Explicit}"/>   By default, when a TwoWay bound control looses focus the value is updated. When you added validation like I’ve shown you earlier, the value is validated. To overcome this, you have to tell the binding update explicitly by setting the UpdateSourceTrigger binding property to Explicit:   private void SubmitButtonClick(object sender, RoutedEventArgs e) { NameField.GetBindingExpression(TextBox.TextProperty).UpdateSource(); }   This way, the binding is in two direction but the source is only updated, thus validated, when you tell it to. In the code behind you have to call the UpdateSource method on the binding expression, which you can get from the TextBox.   Conclusion Data validation is something you’ll probably want on almost every entry form. I always thought it was hard to do, but it wasn’t. If you can throw an exception you can do validation. If you want to know anything more in depth about something I talked about in this article let me know. I might write an entire post to that.

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• Microsoft TypeScript : A Typed Superset of JavaScript

  - by shiju

  JavaScript is gradually becoming a ubiquitous programming language for the web, and the popularity of JavaScript is increasing day by day. Earlier, JavaScript was just a language for browser. But now, we can write JavaScript apps for browser, server and mobile. With the advent of Node.js, you can build scalable, high performance apps on the server with JavaScript. But many developers, especially developers who are working with static type languages, are hating the JavaScript language due to the lack of structuring and the maintainability problems of JavaScript. Microsoft TypeScript is trying to solve some problems of JavaScript when we are building scalable JavaScript apps. Microsoft TypeScript TypeScript is Microsoft's solution for writing scalable JavaScript programs with the help of Static Types, Interfaces, Modules and Classes along with greater tooling support. TypeScript is a typed superset of JavaScript that compiles to plain JavaScript. This would be more productive for developers who are coming from static type languages. You can write scalable JavaScript  apps in TypeScript with more productive and more maintainable manner, and later you can compiles to plain JavaScript which will be run on any browser and any OS. TypeScript will work with browser based JavaScript apps and JavaScript apps that following CommonJS specification. You can use TypeScript for building HTML 5 apps, Node.JS apps, WinRT apps. TypeScript is providing better tooling support with Visual Studio, Sublime Text, Vi, Emacs. Microsoft has open sourced its TypeScript languages on CodePlex at http://typescript.codeplex.com/    Install TypeScript You can install TypeScript compiler as a Node.js package via the NPM or you can install as a Visual Studio 2012 plug-in which will enable you better tooling support within the Visual Studio IDE. Since TypeScript is distributed as a Node.JS package, and it can be installed on other OS such as Linux and MacOS. The following command will install TypeScript compiler via an npm package for node.js npm install –g typescript TypeScript provides a Visual Studio 2012 plug-in as MSI file which will install TypeScript and also provides great tooling support within the Visual Studio, that lets the developers to write TypeScript apps with greater productivity and better maintainability. You can download the Visual Studio plug-in from here Building JavaScript  apps with TypeScript You can write typed version of JavaScript programs with TypeScript and then compiles it to plain JavaScript code. The beauty of the TypeScript is that it is already JavaScript and normal JavaScript programs are valid TypeScript programs, which means that you can write normal  JavaScript code and can use typed version of JavaScript whenever you want. TypeScript files are using extension .ts and this will be compiled using a compiler named tsc. The following is a sample program written in  TypeScript greeter.ts 1: class Greeter { 2: greeting: string; 3: constructor (message: string) { 4: this.greeting = message; 5: } 6: greet() { 7: return "Hello, " + this.greeting; 8: } 9: } 10:   11: var greeter = new Greeter("world"); 12:   13: var button = document.createElement('button') 14: button.innerText = "Say Hello" 15: button.onclick = function() { 16: alert(greeter.greet()) 17: } 18:   19: document.body.appendChild(button) .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The above program is compiling with the TypeScript compiler as shown in the below picture The TypeScript compiler will generate a JavaScript file after compiling the TypeScript program. If your TypeScript programs having any reference to other TypeScript files, it will automatically generate JavaScript files for the each referenced files. The following code block shows the compiled version of plain JavaScript  for the above greeter.ts greeter.js 1: var Greeter = (function () { 2: function Greeter(message) { 3: this.greeting = message; 4: } 5: Greeter.prototype.greet = function () { 6: return "Hello, " + this.greeting; 7: }; 8: return Greeter; 9: })(); 10: var greeter = new Greeter("world"); 11: var button = document.createElement('button'); 12: button.innerText = "Say Hello"; 13: button.onclick = function () { 14: alert(greeter.greet()); 15: }; 16: document.body.appendChild(button); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Tooling Support with Visual Studio TypeScript is providing a plug-in for Visual Studio which will provide an excellent support for writing TypeScript  programs within the Visual Studio. The following screen shot shows the Visual Studio template for TypeScript apps   The following are the few screen shots of Visual Studio IDE for TypeScript apps. Summary TypeScript is Microsoft's solution for writing scalable JavaScript apps which will solve lot of problems involved in larger JavaScript apps. I hope that this solution will attract lot of developers who are really looking for writing maintainable structured code in JavaScript, without losing any productivity. TypeScript lets developers to write JavaScript apps with the help of Static Types, Interfaces, Modules and Classes and also providing better productivity. I am a passionate developer on Node.JS and would definitely try to use TypeScript for building Node.JS apps on the Windows Azure cloud. I am really excited about to writing Node.JS apps by using TypeScript, from my favorite development IDE Visual Studio. You can follow me on twitter at @shijucv

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• Soapi.CS : A fully relational fluent .NET Stack Exchange API client library

  - by Sky Sanders

  Soapi.CS for .Net / Silverlight / Windows Phone 7 / Mono as easy as breathing...: var context = new ApiContext(apiKey).Initialize(false); Question thisPost = context.Official .StackApps .Questions.ById(386) .WithComments(true) .First(); Console.WriteLine(thisPost.Title); thisPost .Owner .Questions .PageSize(5) .Sort(PostSort.Votes) .ToList() .ForEach(q=> { Console.WriteLine("\t" + q.Score + "\t" + q.Title); q.Timeline.ToList().ForEach(t=> Console.WriteLine("\t\t" + t.TimelineType + "\t" + t.Owner.DisplayName)); Console.WriteLine(); }); // if you can think it, you can get it. Output Soapi.CS : A fully relational fluent .NET Stack Exchange API client library 21 Soapi.CS : A fully relational fluent .NET Stack Exchange API client library Revision code poet Revision code poet Votes code poet Votes code poet Revision code poet Revision code poet Revision code poet Votes code poet Votes code poet Votes code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Revision code poet Votes code poet Comment code poet Revision code poet Votes code poet Revision code poet Revision code poet Revision code poet Answer code poet Revision code poet Revision code poet 14 SOAPI-WATCH: A realtime service that notifies subscribers via twitter when the API changes in any way. Votes code poet Revision code poet Votes code poet Comment code poet Comment code poet Comment code poet Votes lfoust Votes code poet Comment code poet Comment code poet Comment code poet Comment code poet Revision code poet Comment lfoust Votes code poet Revision code poet Votes code poet Votes lfoust Votes code poet Revision code poet Comment Dave DeLong Revision code poet Revision code poet Votes code poet Comment lfoust Comment Dave DeLong Comment lfoust Comment lfoust Comment Dave DeLong Revision code poet 11 SOAPI-EXPLORE: Self-updating single page JavaSript API test harness Votes code poet Votes code poet Votes code poet Votes code poet Votes code poet Comment code poet Revision code poet Votes code poet Revision code poet Revision code poet Revision code poet Comment code poet Revision code poet Votes code poet Comment code poet Question code poet Votes code poet 11 Soapi.JS V1.0: fluent JavaScript wrapper for the StackOverflow API Comment George Edison Comment George Edison Comment George Edison Comment George Edison Comment George Edison Comment George Edison Answer George Edison Votes code poet Votes code poet Votes code poet Votes code poet Revision code poet Revision code poet Answer code poet Comment code poet Revision code poet Comment code poet Comment code poet Comment code poet Revision code poet Revision code poet Votes code poet Votes code poet Votes code poet Votes code poet Comment code poet Comment code poet Comment code poet Comment code poet Comment code poet 9 SOAPI-DIFF: Your app broke? Check SOAPI-DIFF to find out what changed in the API Votes code poet Revision code poet Comment Dennis Williamson Answer Dennis Williamson Votes code poet Votes Dennis Williamson Comment code poet Question code poet Votes code poet About A robust, fully relational, easy to use, strongly typed, end-to-end StackOverflow API Client Library. Out of the box, Soapi provides you with a robust client library that abstracts away most all of the messy details of consuming the API and lets you concentrate on implementing your ideas. A few features include: A fully relational model of the API data set exposed via a fully 'dot navigable' IEnumerable (LINQ) implementation. Simply tell Soapi what you want and it will get it for you. e.g. "On my first question, from the author of the first comment, get the first page of comments by that person on any post" my.Questions.First().Comments.First().Owner.Comments.ToList(); (yes this is a real expression that returns the data as expressed!) Full coverage of the API, all routes and all parameters with an intuitive syntax. Strongly typed Domain Data Objects for all API data structures. Eager and Lazy Loading of 'stub' objects. Eager\Lazy loading may be disabled. When finer grained control of requests is desired, the core RouteMap objects may be leveraged to request data from any of the API paths using all available parameters as documented on the help pages. A rich Asynchronous implementation. A configurable request cache to reduce unnecessary network traffic and to simplify your usage logic. There is no need to go out of your way to be frugal. You may set a distinct cache duration for any particular route. A configurable request throttle to ensure compliance with the api terms of usage and to simplify your code in that you do not have to worry about and respond to 50X errors. The RequestCache and Throttled Queue are thread-safe, so can make as many requests as you like from as many threads as you like as fast as you like and not worry about abusing the api or having to write reams of management/compensation code. Configurable retry threshold that will, by default, make up to 3 attempts to retrieve a request before failing. Every request made by Soapi is properly formed and directed so most any http error will be the result of a timeout or other network infrastructure. A retry buffer provides a level of fault tolerance that you can rely on. An almost identical javascript library, Soapi.JS, and it's full figured big brother, Soapi.JS2, that will enable you to leverage your server cycles and bandwidth for only those tasks that require it and offload things like status updates to the client's browser. License Licensed GPL Version 2 license. Why is Soapi.CS GPL? Can I get an LGPL license for Soapi.CS? (hint: probably) Platforms .NET 3.5 .NET 4.0 Silverlight 3 Silverlight 4 Windows Phone 7 Mono Download Source code lives @ http://soapics.codeplex.com. Binary releases are forthcoming. codeplex is acting up again. get the source and binaries @ http://bitbucket.org/bitpusher/soapi.cs/downloads The source is C# 3.5. and includes projects and solutions for the following IDEs Visual Studio 2008 Visual Studio 2010 ModoDevelop 2.4 Documentation Full documentation is available at http://soapi.info/help/cs/index.aspx Sample Code / Usage Examples Sample code and usage examples will be added as answers to this question. Full API Coverage all API routes are covered Full Parameter Parity If the API exposes it, Soapi giftwraps it for you. Building a simple app with Soapi.CS - a simple app that gathers all traces of a user in the whole stackiverse. Fluent Configuration - Setting up a Soapi.ApiContext could not be easier Bulk Data Import - A tiny app that quickly loads a SQLite data file with all users in the stackiverse. Paged Results - Soapi.CS transparently handles multi-page operations. Asynchronous Requests - Soapi.CS provides a rich asynchronous model that is especially useful when writing api apps in Silverlight or Windows Phone 7. Caching and Throttling - how and why Apps that use Soapi.CS Soapi.FindUser - .net utility for locating a user anywhere in the stackiverse Soapi.Explore - The entire API at your command Soapi.LastSeen - List users by last access time Add your app/site here - I know you are out there ;-) if you are not comfortable editing this post, simply add a comment and I will add it. The CS/SL/WP7/MONO libraries all compile the same code and with the exception of environmental considerations of Silverlight, the code samples are valid for all libraries. You may also find guidance in the test suites. More information on the SOAPI eco-system. Contact This library is currently the effort of me, Sky Sanders (code poet) and can be reached at gmail - sky.sanders Any who are interested in improving this library are welcome. Support Soapi You can help support this project by voting for Soapi's Open Source Ad post For more information about the origins of Soapi.CS and the rest of the Soapi eco-system see What is Soapi and why should I care?

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• SQL SERVER – How to Recover SQL Database Data Deleted by Accident

  - by Pinal Dave

  In Repair a SQL Server database using a transaction log explorer, I showed how to use ApexSQL Log, a SQL Server transaction log viewer, to recover a SQL Server database after a disaster. In this blog, I’ll show you how to use another SQL Server disaster recovery tool from ApexSQL in a situation when data is accidentally deleted. You can download ApexSQL Recover here, install, and play along. With a good SQL Server disaster recovery strategy, data recovery is not a problem. You have a reliable full database backup with valid data, a full database backup and subsequent differential database backups, or a full database backup and a chain of transaction log backups. But not all situations are ideal. Here we’ll address some sub-optimal scenarios, where you can still successfully recover data. If you have only a full database backup This is the least optimal SQL Server disaster recovery strategy, as it doesn’t ensure minimal data loss. For example, data was deleted on Wednesday. Your last full database backup was created on Sunday, three days before the records were deleted. By using the full database backup created on Sunday, you will be able to recover SQL database records that existed in the table on Sunday. If there were any records inserted into the table on Monday or Tuesday, they will be lost forever. The same goes for records modified in this period. This method will not bring back modified records, only the old records that existed on Sunday. If you restore this full database backup, all your changes (intentional and accidental) will be lost and the database will be reverted to the state it had on Sunday. What you have to do is compare the records that were in the table on Sunday to the records on Wednesday, create a synchronization script, and execute it against the Wednesday database. If you have a full database backup followed by differential database backups Let’s say the situation is the same as in the example above, only you create a differential database backup every night. Use the full database backup created on Sunday, and the last differential database backup (created on Tuesday). In this scenario, you will lose only the data inserted and updated after the differential backup created on Tuesday. If you have a full database backup and a chain of transaction log backups This is the SQL Server disaster recovery strategy that provides minimal data loss. With a full chain of transaction logs, you can recover the SQL database to an exact point in time. To provide optimal results, you have to know exactly when the records were deleted, because restoring to a later point will not bring back the records. This method requires restoring the full database backup first. If you have any differential log backup created after the last full database backup, restore the most recent one. Then, restore transaction log backups, one by one, it the order they were created starting with the first created after the restored differential database backup. Now, the table will be in the state before the records were deleted. You have to identify the deleted records, script them and run the script against the original database. Although this method is reliable, it is time-consuming and requires a lot of space on disk. How to easily recover deleted records? The following solution enables you to recover SQL database records even if you have no full or differential database backups and no transaction log backups. To understand how ApexSQL Recover works, I’ll explain what happens when table data is deleted. Table data is stored in data pages. When you delete table records, they are not immediately deleted from the data pages, but marked to be overwritten by new records. Such records are not shown as existing anymore, but ApexSQL Recover can read them and create undo script for them. How long will deleted records stay in the MDF file? It depends on many factors, as time passes it’s less likely that the records will not be overwritten. The more transactions occur after the deletion, the more chances the records will be overwritten and permanently lost. Therefore, it’s recommended to create a copy of the database MDF and LDF files immediately (if you cannot take your database offline until the issue is solved) and run ApexSQL Recover on them. Note that a full database backup will not help here, as the records marked for overwriting are not included in the backup. First, I’ll delete some records from the Person.EmailAddress table in the AdventureWorks database.   I can delete these records in SQL Server Management Studio, or execute a script such as DELETE FROM Person.EmailAddress WHERE BusinessEntityID BETWEEN 70 AND 80 Then, I’ll start ApexSQL Recover and select From DELETE operation in the Recovery tab.   In the Select the database to recover step, first select the SQL Server instance. If it’s not shown in the drop-down list, click the Server icon right to the Server drop-down list and browse for the SQL Server instance, or type the instance name manually. Specify the authentication type and select the database in the Database drop-down list.   In the next step, you’re prompted to add additional data sources. As this can be a tricky step, especially for new users, ApexSQL Recover offers help via the Help me decide option.   The Help me decide option guides you through a series of questions about the database transaction log and advises what files to add. If you know that you have no transaction log backups or detached transaction logs, or the online transaction log file has been truncated after the data was deleted, select No additional transaction logs are available. If you know that you have transaction log backups that contain the delete transactions you want to recover, click Add transaction logs. The online transaction log is listed and selected automatically.   Click Add if to add transaction log backups. It would be best if you have a full transaction log chain, as explained above. The next step for this option is to specify the time range.   Selecting a small time range for the time of deletion will create the recovery script just for the accidentally deleted records. A wide time range might script the records deleted on purpose, and you don’t want that. If needed, you can check the script generated and manually remove such records. After that, for all data sources options, the next step is to select the tables. Be careful here, if you deleted some data from other tables on purpose, and don’t want to recover them, don’t select all tables, as ApexSQL Recover will create the INSERT script for them too.   The next step offers two options: to create a recovery script that will insert the deleted records back into the Person.EmailAddress table, or to create a new database, create the Person.EmailAddress table in it, and insert the deleted records. I’ll select the first one.   The recovery process is completed and 11 records are found and scripted, as expected.   To see the script, click View script. ApexSQL Recover has its own script editor, where you can review, modify, and execute the recovery script. The insert into statements look like: INSERT INTO Person.EmailAddress( BusinessEntityID, EmailAddressID, EmailAddress, rowguid, ModifiedDate) VALUES( 70, 70, N'[email protected]' COLLATE SQL_Latin1_General_CP1_CI_AS, 'd62c5b4e-c91f-403f-b630-7b7e0fda70ce', '20030109 00:00:00.000' ); To execute the script, click Execute in the menu.   If you want to check whether the records are really back, execute SELECT * FROM Person.EmailAddress WHERE BusinessEntityID BETWEEN 70 AND 80 As shown, ApexSQL Recover recovers SQL database data after accidental deletes even without the database backup that contains the deleted data and relevant transaction log backups. ApexSQL Recover reads the deleted data from the database data file, so this method can be used even for databases in the Simple recovery model. Besides recovering SQL database records from a DELETE statement, ApexSQL Recover can help when the records are lost due to a DROP TABLE, or TRUNCATE statement, as well as repair a corrupted MDF file that cannot be attached to as SQL Server instance. You can find more information about how to recover SQL database lost data and repair a SQL Server database on ApexSQL Solution center. There are solutions for various situations when data needs to be recovered. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• How can I get penetration depth from Minkowski Portal Refinement / Xenocollide?

  - by Raven Dreamer

  I recently got an implementation of Minkowski Portal Refinement (MPR) successfully detecting collision. Even better, my implementation returns a good estimate (local minimum) direction for the minimum penetration depth. So I took a stab at adjusting the algorithm to return the penetration depth in an arbitrary direction, and was modestly successful - my altered method works splendidly for face-edge collision resolution! What it doesn't currently do, is correctly provide the minimum penetration depth for edge-edge scenarios, such as the case on the right: What I perceive to be happening, is that my current method returns the minimum penetration depth to the nearest vertex - which works fine when the collision is actually occurring on the plane of that vertex, but not when the collision happens along an edge. Is there a way I can alter my method to return the penetration depth to the point of collision, rather than the nearest vertex? Here's the method that's supposed to return the minimum penetration distance along a specific direction: public static Vector3 CalcMinDistance(List<Vector3> shape1, List<Vector3> shape2, Vector3 dir) { //holding variables Vector3 n = Vector3.zero; Vector3 swap = Vector3.zero; // v0 = center of Minkowski sum v0 = Vector3.zero; // Avoid case where centers overlap -- any direction is fine in this case //if (v0 == Vector3.zero) return Vector3.zero; //always pass in a valid direction. // v1 = support in direction of origin n = -dir; //get the differnce of the minkowski sum Vector3 v11 = GetSupport(shape1, -n); Vector3 v12 = GetSupport(shape2, n); v1 = v12 - v11; //if the support point is not in the direction of the origin if (v1.Dot(n) <= 0) { //Debug.Log("Could find no points this direction"); return Vector3.zero; } // v2 - support perpendicular to v1,v0 n = v1.Cross(v0); if (n == Vector3.zero) { //v1 and v0 are parallel, which means //the direction leads directly to an endpoint n = v1 - v0; //shortest distance is just n //Debug.Log("2 point return"); return n; } //get the new support point Vector3 v21 = GetSupport(shape1, -n); Vector3 v22 = GetSupport(shape2, n); v2 = v22 - v21; if (v2.Dot(n) <= 0) { //can't reach the origin in this direction, ergo, no collision //Debug.Log("Could not reach edge?"); return Vector2.zero; } // Determine whether origin is on + or - side of plane (v1,v0,v2) //tests linesegments v0v1 and v0v2 n = (v1 - v0).Cross(v2 - v0); float dist = n.Dot(v0); // If the origin is on the - side of the plane, reverse the direction of the plane if (dist > 0) { //swap the winding order of v1 and v2 swap = v1; v1 = v2; v2 = swap; //swap the winding order of v11 and v12 swap = v12; v12 = v11; v11 = swap; //swap the winding order of v11 and v12 swap = v22; v22 = v21; v21 = swap; //and swap the plane normal n = -n; } /// // Phase One: Identify a portal while (true) { // Obtain the support point in a direction perpendicular to the existing plane // Note: This point is guaranteed to lie off the plane Vector3 v31 = GetSupport(shape1, -n); Vector3 v32 = GetSupport(shape2, n); v3 = v32 - v31; if (v3.Dot(n) <= 0) { //can't enclose the origin within our tetrahedron //Debug.Log("Could not reach edge after portal?"); return Vector3.zero; } // If origin is outside (v1,v0,v3), then eliminate v2 and loop if (v1.Cross(v3).Dot(v0) < 0) { //failed to enclose the origin, adjust points; v2 = v3; v21 = v31; v22 = v32; n = (v1 - v0).Cross(v3 - v0); continue; } // If origin is outside (v3,v0,v2), then eliminate v1 and loop if (v3.Cross(v2).Dot(v0) < 0) { //failed to enclose the origin, adjust points; v1 = v3; v11 = v31; v12 = v32; n = (v3 - v0).Cross(v2 - v0); continue; } bool hit = false; /// // Phase Two: Refine the portal int phase2 = 0; // We are now inside of a wedge... while (phase2 < 20) { phase2++; // Compute normal of the wedge face n = (v2 - v1).Cross(v3 - v1); n.Normalize(); // Compute distance from origin to wedge face float d = n.Dot(v1); // If the origin is inside the wedge, we have a hit if (d > 0 ) { //Debug.Log("Do plane test here"); float T = n.Dot(v2) / n.Dot(dir); Vector3 pointInPlane = (dir * T); return pointInPlane; } // Find the support point in the direction of the wedge face Vector3 v41 = GetSupport(shape1, -n); Vector3 v42 = GetSupport(shape2, n); v4 = v42 - v41; float delta = (v4 - v3).Dot(n); float separation = -(v4.Dot(n)); if (delta <= kCollideEpsilon || separation >= 0) { //Debug.Log("Non-convergance detected"); //Debug.Log("Do plane test here"); return Vector3.zero; } // Compute the tetrahedron dividing face (v4,v0,v1) float d1 = v4.Cross(v1).Dot(v0); // Compute the tetrahedron dividing face (v4,v0,v2) float d2 = v4.Cross(v2).Dot(v0); // Compute the tetrahedron dividing face (v4,v0,v3) float d3 = v4.Cross(v3).Dot(v0); if (d1 < 0) { if (d2 < 0) { // Inside d1 & inside d2 ==> eliminate v1 v1 = v4; v11 = v41; v12 = v42; } else { // Inside d1 & outside d2 ==> eliminate v3 v3 = v4; v31 = v41; v32 = v42; } } else { if (d3 < 0) { // Outside d1 & inside d3 ==> eliminate v2 v2 = v4; v21 = v41; v22 = v42; } else { // Outside d1 & outside d3 ==> eliminate v1 v1 = v4; v11 = v41; v12 = v42; } } } return Vector3.zero; } }

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• Package Dependencies Error in almost every install

  - by Betaxpression

  New to Ubuntu. In the other sofware sources i have "Debian 4.0 eth" officially supported "non-us.debian.org/"; etc ... "ppa.launcpad.net" and installing applications has stopped working. I think i first came across this problem after installing Blender 2.58 When using update manager it is prompting for a partial upgrade. Almost every software when trying to install showing the same error Package Dependencies Error or GPG PUB KEY missing, tried to fixing to them but no luck. Output to: sudo apt-get update && sudo apt-get upgrade (links disabled http:// -- http:/ as new user can't put more no. of hyperlinks) Ign http:/non-us.debian.org stable/non-US InRelease Ign http:/non-us.debian.org stable/non-US Release.gpg Ign http:/non-us.debian.org stable/non-US Release Ign http:/non-us.debian.org stable/non-US/contrib TranslationIndex Ign http:/non-us.debian.org stable/non-US/main TranslationIndex Ign http:/non-us.debian.org stable/non-US/non-free TranslationIndex Err http:/non-us.debian.org stable/non-US/main Sources 503 Service Unavailable Err http:/non-us.debian.org stable/non-US/contrib Sources 503 Service Unavailable Err http:/non-us.debian.org stable/non-US/non-free Sources 503 Service Unavailable Err http:/non-us.debian.org stable/non-US/main amd64 Packages 503 Service Unavailable Err http:/non-us.debian.org stable/non-US/contrib amd64 Packages 503 Service Unavailable Err http:/non-us.debian.org stable/non-US/non-free amd64 Packages 503 Service Unavailable Ign http:/non-us.debian.org stable/non-US/contrib Translation-en_IN Ign http:/non-us.debian.org stable/non-US/contrib Translation-en Ign http:/non-us.debian.org stable/non-US/main Translation-en_IN Ign http:/non-us.debian.org stable/non-US/main Translation-en Ign http:/non-us.debian.org stable/non-US/non-free Translation-en_IN Ign http:/non-us.debian.org stable/non-US/non-free Translation-en Ign http:/archive.ubuntu.com natty InRelease Ign http:/archive.canonical.com natty InRelease Ign http:/extras.ubuntu.com natty InRelease Ign http:/http.us.debian.org stable InRelease Ign http:/ftp.us.debian.org etch InRelease Ign http:/archive.ubuntu.com natty-updates InRelease Hit http:/archive.canonical.com natty Release.gpg Get:1 http:/extras.ubuntu.com natty Release.gpg [72 B] Ign http:/ppa.launchpad.net natty InRelease Get:2 http:/http.us.debian.org stable Release.gpg [1,672 B] Ign http:/linux.dropbox.com natty InRelease Ign http:/ftp.us.debian.org etch Release.gpg Ign http:/archive.ubuntu.com natty-security InRelease Hit http:/archive.canonical.com natty Release Hit http:/extras.ubuntu.com natty Release Ign http:/ppa.launchpad.net natty InRelease Get:3 http:/linux.dropbox.com natty Release.gpg [489 B] Ign http:/ftp.us.debian.org etch Release Ign http:/dl.google.com stable InRelease Get:4 http:/archive.ubuntu.com natty Release.gpg [198 B] Ign http:/ppa.launchpad.net natty InRelease Hit http:/archive.canonical.com natty/partner Sources Hit http:/extras.ubuntu.com natty/main Sources Get:5 http:/linux.dropbox.com natty Release [2,599 B] Get:6 http:/archive.ubuntu.com natty-updates Release.gpg [198 B] Ign http:/ppa.launchpad.net natty InRelease Hit http:/archive.canonical.com natty/partner amd64 Packages Hit http:/extras.ubuntu.com natty/main amd64 Packages Get:7 http:/linux.dropbox.com natty/main amd64 Packages [784 B] Get:8 http:/archive.ubuntu.com natty-security Release.gpg [198 B] Ign http:/ppa.launchpad.net natty InRelease Ign http:/archive.canonical.com natty/partner TranslationIndex Ign http:/extras.ubuntu.com natty/main TranslationIndex Get:9 http:/http.us.debian.org stable Release [104 kB] Ign http:/linux.dropbox.com natty/main TranslationIndex Hit http:/archive.ubuntu.com natty Release Ign http:/ppa.launchpad.net natty InRelease Ign http:/http.us.debian.org stable Release Hit http:/archive.ubuntu.com natty-updates Release Get:10 http:/ppa.launchpad.net natty InRelease [316 B] Ign http:/ppa.launchpad.net natty InRelease Hit http:/archive.ubuntu.com natty-security Release Get:11 http:/ppa.launchpad.net natty InRelease [316 B] Ign http:/ppa.launchpad.net natty InRelease Hit http:/archive.ubuntu.com natty/restricted Sources Get:12 http:/ppa.launchpad.net natty Release.gpg [316 B] Ign http:/http.us.debian.org stable/main Sources/DiffIndex Get:13 http:/ppa.launchpad.net natty Release.gpg [316 B] Hit http:/archive.ubuntu.com natty/main Sources Ign http:/ftp.us.debian.org etch/contrib TranslationIndex Ign http:/http.us.debian.org stable/contrib Sources/DiffIndex Get:14 http:/ppa.launchpad.net natty Release.gpg [1,502 B] Ign http:/http.us.debian.org stable/non-free Sources/DiffIndex Ign http:/ftp.us.debian.org etch/main TranslationIndex Get:15 http:/ppa.launchpad.net natty Release.gpg [1,928 B] Ign http:/http.us.debian.org stable/main amd64 Packages/DiffIndex Ign http:/ftp.us.debian.org etch/non-free TranslationIndex Ign http:/ppa.launchpad.net natty Release.gpg Hit http:/http.us.debian.org stable/contrib amd64 Packages/DiffIndex W: GPG error: http:/http.us.debian.org stable Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY AED4B06F473041FA NO_PUBKEY 64481591B98321F9 W: GPG error: http:/ppa.launchpad.net natty InRelease: File /var/lib/apt/lists/partial/ppa.launchpad.net_sunab_kdenlive-release_ubuntu_dists_natty_InRelease doesn't start with a clearsigned message W: GPG error: http:/ppa.launchpad.net natty InRelease: File /var/lib/apt/lists/partial/ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_natty_InRelease doesn't start with a clearsigned message E: Could not open file /var/lib/apt/lists/http.us.debian.org_debian_dists_stable_contrib_binary-amd64_Packages.IndexDiff - open (2: No such file or directory) output to: sudo cat /etc/apt/sources.list # deb cdrom:[Ubuntu 11.04 _Natty Narwhal_ - Release amd64 (20110427.1)]/ natty main restricted # See http:/help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http:/archive.ubuntu.com/ubuntu natty main restricted deb-src http:/archive.ubuntu.com/ubuntu natty restricted main multiverse universe #Added by software-properties ## Major bug fix updates produced after the final release of the ## distribution. deb http:/archive.ubuntu.com/ubuntu natty-updates main restricted deb-src http:/archive.ubuntu.com/ubuntu natty-updates restricted main multiverse universe #Added by software-properties ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http:/archive.ubuntu.com/ubuntu natty universe deb http:/archive.ubuntu.com/ubuntu natty-updates universe ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http:/archive.ubuntu.com/ubuntu natty multiverse deb http:/archive.ubuntu.com/ubuntu natty-updates multiverse ## Uncomment the following two lines to add software from the 'backports' ## repository. ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. # deb http:/us.archive.ubuntu.com/ubuntu/ natty-backports main restricted universe multiverse # deb-src http:/us.archive.ubuntu.com/ubuntu/ natty-backports main restricted universe multiverse deb http:/archive.ubuntu.com/ubuntu natty-security main restricted deb-src http:/archive.ubuntu.com/ubuntu natty-security restricted main multiverse universe #Added by software-properties deb http:/archive.ubuntu.com/ubuntu natty-security universe deb http:/archive.ubuntu.com/ubuntu natty-security multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http:/archive.canonical.com/ubuntu natty partner deb-src http:/archive.canonical.com/ubuntu natty partner ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software. deb http:/extras.ubuntu.com/ubuntu natty main deb-src http:/extras.ubuntu.com/ubuntu natty main deb http:/ftp.us.debian.org/debian/ etch main contrib non-free deb-src http:/ftp.us.debian.org/debian/ etch main contrib non-free deb http:/http.us.debian.org/debian stable main contrib non-free deb-src http:/http.us.debian.org/debian stable main contrib non-free deb http:/non-us.debian.org/debian-non-US stable/non-US main contrib non-free deb-src http:/non-us.debian.org/debian-non-US stable/non-US main contrib non-free Thanks But after removing Debian repositories still getting this error: W:GPG error: http://ppa.launchpad.net natty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 9BDB3D89CE49EC21, W:GPG error: http://ppa.launchpad.net natty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 80E7349A06ED541C, W:GPG error: http://ppa.launchpad.net natty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8C851674F96FD737, W:GPG error: http://ppa.launchpad.net natty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 94E58C34A8670E8C, E:Unable to parse package file /var/lib/apt/lists/partial/archive.ubuntu.com_ubuntu_dists_natty-updates_multiverse_i18n_Index (1) I actually tried this before, but i am always getting this error --Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv-keys 8C851674F96FD737 gpg: requesting key F96FD737 from hkp server keyserver.ubuntu.com ?: keyserver.ubuntu.com: Connection refused gpgkeys: HTTP fetch error 7: couldn't connect: Connection refused gpg: no valid OpenPGP data found. gpg: Total number processed: 0

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• What does it mean when a User-Agent has another User-Agent inside it?

  - by Erx_VB.NExT.Coder

  Basically, sometimes the user-agent will have its normal user-agent displayed, then at the end it will have teh "User-Agent: " tag displayed, and right after it another user-agent is shown. Sometimes, the second user-agent is just appended to the first one without the "User-Agent: " tag. Here are some samples I've seen: The first few contain the "User-Agent: " tag in the middle somewhere, and I've changed its font to make it easier to to see. Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; Trident/4.0; GTB6; User-agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); SLCC1; .NET CLR 2.0.50727; .NET CLR 3.0.04506) Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB6; MRA 5.10 (build 5339); User-agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); .NET CLR 1.1.4322; .NET CLR 2.0.50727) Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; User-agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729) Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; User-agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152) Here are some without the "User-Agent: " tag in the middle, but just two user agents that seem stiched together. Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); .NET CLR 3.5.30729) Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB6; IPMS/6568080A-04A5AD839A9; TCO_20090713170733; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1); InfoPath.2) Now, just to add a few notes to this. I understand that the "User-Agent: " tag is normally a header, and what follows a typical "User-Agent: " string sequence is the actual user agent that is sent to servers etc, but normally the "User-Agent: " string should not be part of the actual user agent, that is more like the pre-fix or a tag indicating that what follows will be the actual user agent. Additionally, I may have thought, hey, these are just two user agents pasted together, but on closer inspection, you realize that they are not. On all of these dual user agent listings, if you look at the opening bracket "(" just before the "compatible" keyword, you realize the pair to that bracket ")" is actually at the very end, the end of the second user agent. So, the first user agents closing bracket ")" never occurs before the second user agent begins, it's always right at the end, and therefore, the second user agent is more like one of the features of the first user agent, like: "Trident/4.0" or "GTB6" etc etc... The other thing to note that the second user agent is always MSIE 6.0 (Internet Explorer 6.0), interesting. What I had initially thought was it's some sort of Virtual Machine displaying the browser in use & the browser that is installed, but then I thought, what'd be the point in that? Finally, right now, I am thinking, it's probably soem sort of "Compatibility View" type thing, where even if MSIE 7.0 or 8.0 is installed, when my hypothetical the "Display In Internet Explorer 6.0" mode is turned on, the user agent changes to something like this. That being, IE 8.0 is installed, but is rendering everything as IE 6.0 would. Is there or was there such a feature in Internet Explorer? Am I on to something here? What are your thoughts on this? If you have any other ideas, please feel free to let us know. At the moment, I'm just trying to understand if these are valid User Agents, or if they are invalid. In a list of about 44,000 User Agents, I've seen this type of Dual User Agent about 400 times. I've closely inspected 40 of them, and every single one had MSIE 6.0 as the "second" user agent (and the first user agent a higher version of MSIE, such as 7 or 8). This was true for all except one, where both user agents were MSIE 8.0, here it is: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 8.0; Win32; GMX); GTB0.0) This occured once in my 40 "close" inspections. I've estimated the 400 in 44,000 by taking a sample of the first 4,400 user agents, and finding 40 of these in the MSIE/Windows user agents, and extrapolated that to estimate 40. There were also similar things occuring for non MSIE user agents where there were two Mozilla's in one user agent, the non MSIE ones would probably add another 30% on top of the ones I've noted. I can show you samples of them if anyone would like. There we have it, this is where I'm at, what do you guys think?

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• C# in Depth, Third Edition by Jon Skeet, Manning Publications Co. Book Review

  - by Compudicted

  Originally posted on: http://geekswithblogs.net/Compudicted/archive/2013/10/24/c-in-depth-third-edition-by-jon-skeet-manning-publications.aspx I started reading this ebook on September 28, 2013, the same day it was sent my way by Manning Publications Co. for review while it still being fresh off the press. So 1st thing – thanks to Manning for this opportunity and a free copy of this must have on every C# developer’s desk book! Several hours ago I finished reading this book (well, except a for a large portion of its quite lengthy appendix). I jumped writing this review right away while still being full of emotions and impressions from reading it thoroughly and running code examples. Before I go any further I would like say that I used to program on various platforms using various languages starting with the Mainframe and ending on Windows, and I gradually shifted toward dealing with databases more than anything, however it happened with me to program in C# 1 a lot when it was first released and then some C# 2 with a big leap in between to C# 5. So my perception and experience reading this book may differ from yours. Also what I want to tell is somewhat funny that back then, knowing some Java and seeing C# 1 released, initially made me drawing a parallel that it is a copycat language, how wrong was I… Interestingly, Jon programs in Java full time, but how little it was mentioned in the book! So more on the book: Be informed, this is not a typical “Recipes”, “Cookbook” or any set of ready solutions, it is rather targeting mature, advanced developers who do not only know how to use a number of features, but are willing to understand how the language is operating “under the hood”. I must state immediately, at the same time I am glad the author did not go into the murky depths of the MSIL, so this is a very welcome decision on covering a modern language as C# for me, thank you Jon! Frankly, not all was that rosy regarding the tone and structure of the book, especially the the first half or so filled me with several negative and positive emotions overpowering each other. To expand more on that, some statements in the book appeared to be bias to me, or filled with pre-justice, it started to look like it had some PR-sole in it, but thankfully this was all gone toward the end of the 1st third of the book. Specifically, the mention on the C# language popularity, Java is the #1 language as per https://sites.google.com/site/pydatalog/pypl/PyPL-PopularitY-of-Programming-Language (many other sources put C at the top which I highly doubt), also many interesting functional languages as Clojure and Groovy appeared and gained huge traction which run on top of Java/JVM whereas C# does not enjoy such a situation. If we want to discuss the popularity in general and say how fast a developer can find a new job that pays well it would be indeed the very Java, C++ or PHP, never C#. Or that phrase on language preference as a personal issue? We choose where to work or we are chosen because of a technology used at a given software shop, not vice versa. The book though it technically very accurate with valid code, concise examples, but I wish the author would give more concrete, real-life examples on where each feature should be used, not how. Another point to realize before you get the book is that it is almost a live book which started to be written when even C# 3 wasn’t around so a lot of ground is covered (nearly half of the book) on the pre-C# 3 feature releases so if you already have a solid background in the previous releases and do not plan to upgrade, perhaps half of the book can be skipped, otherwise this book is surely highly recommended. Alas, for me it was a hard read, most of it. It was not boring (well, only may be two times), it was just hard to grasp some concepts, but do not get me wrong, it did made me pause, on several occasions, and made me read and re-read a page or two. At times I even wondered if I have any IQ at all (LOL). Be prepared to read A LOT on generics, not that they are widely used in the field (I happen to work as a consultant and went thru a lot of code at many places) I can tell my impression is the developers today in best case program using examples found at OpenStack.com. Also unlike the Java world where having the most recent version is nearly mandated by the OSS most companies on the Microsoft platform almost never tempted to upgrade the .Net version very soon and very often. As a side note, I was glad to see code recently that included a nullable variable (myvariable? notation) and this made me smile, besides, I recommended that person this book to expand her knowledge. The good things about this book is that Jon maintains an active forum, prepared code snippets and even a small program (Snippy) that is happy to run the sample code saving you from writing any plumbing code. A tad now on the C# language itself – it sure enjoyed a wonderful road toward perfection and a very high adoption, especially for ASP development. But to me all the recent features that made this statically typed language more dynamic look strange. Don’t we have F#? Which supposed to be the dynamic language? Why do we need to have a hybrid language? Now the developers live their lives in dualism of the static and dynamic variables! And LINQ to SQL, it is covered in depth, but wasn’t it supposed to be dropped? Also it seems that very little is being added, and at a slower pace, e.g. Roslyn will come in late 2014 perhaps, and will be probably the only main feature. Again, it is quite hard to read this book as various chapters, C# versions mentioned every so often only if I only could remember what was covered exactly where! So the fact it has so many jumps/links back and forth I recommend the ebook format to make the navigations easier to perform and I do recommend using software that allows bookmarking, also make sure you have access to plenty of coffee and pizza (hey, you probably know this joke – who a programmer is) ! In terms of closing, if you stuck at C# 1 or 2 level, it is time to embrace the power of C# 5! Finally, to compliment Manning, this book unlike from any other publisher so far, was the only one as well readable (put it formatted) on my tablet as in Adobe Reader on a laptop.

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