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  • what is the wrong with this code"length indicator implementation" ?

    - by cj
    Hello, this is an implementation of length indicator field but it hang and i think stuck at a loop and don't show any thing. // readx22.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include "iostream" #include "fstream" #include "stdio.h" using namespace std; class Student { public: string id; size_t id_len; string first_name; size_t first_len; string last_name; size_t last_len; string phone; size_t phone_len; string grade; size_t grade_len; void read(fstream &ven); void print(); }; void Student::read(fstream &ven) { size_t cnt; ven >> cnt; id_len=cnt; id.reserve( cnt ); while ( -- cnt ) { id.push_back( ven.get() ); } ven >> cnt; first_len=cnt; first_name.reserve( cnt ); while ( -- cnt ) { first_name.push_back( ven.get() ); } ven >> cnt; last_len=cnt; last_name.reserve( cnt ); while ( -- cnt ) { last_name.push_back( ven.get() ); } ven >> cnt; phone_len=cnt; phone.reserve( cnt ); while ( -- cnt ) { phone.push_back( ven.get() ); } ven >> cnt; grade_len=cnt; grade.reserve( cnt ); while ( -- cnt ) { grade.push_back( ven.get() ); } } void Student::print() { // string::iterator it; for ( int i=0 ; i<id_len; i++) cout << id[i]; } int main() { fstream in; in.open ("fee.txt", fstream::in); Student x; x.read(in); x.print(); return 0; } thanks

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  • C# Interface Method calls from a controller

    - by ArjaaAine
    I was just working on some application architecture and this may sound like a stupid question but please explain to me how the following works: Interface: public interface IMatterDAL { IEnumerable<Matter> GetMattersByCode(string input); IEnumerable<Matter> GetMattersBySearch(string input); } Class: public class MatterDAL : IMatterDAL { private readonly Database _db; public MatterDAL(Database db) { _db = db; LoadAll(); //Private Method } public virtual IEnumerable<Matter> GetMattersBySearch(string input) { //CODE return result; } public virtual IEnumerable<Matter> GetMattersByCode(string input) { //CODE return results; } Controller: public class MatterController : ApiController { private readonly IMatterDAL _publishedData; public MatterController(IMatterDAL publishedData) { _publishedData = publishedData; } [ValidateInput(false)] public JsonResult SearchByCode(string id) { var searchText = id; //better name for this var results = _publishedData.GetMattersBySearch(searchText).Select( matter => new { MatterCode = matter.Code, MatterName = matter.Name, matter.ClientCode, matter.ClientName }); return Json(results); } This works, when I call my controller method from jquery and step into it, the call to the _publishedData method, goes into the class MatterDAL. I want to know how does my controller know to go to the MatterDAL implementation of the Interface IMatterDAL. What if I have another class called MatterDAL2 which is based on the interface. How will my controller know then to call the right method? I am sorry if this is a stupid question, this is baffling me.

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  • How to completely ignore linkbreak and tab in RegEx?

    - by Kthurein
    Hi, Is there any way to completely ignore link break and tab characters etc. in RegEx? For instance, the line break and tab characters could be found anywhere and in any order in the content string. ... [CustomToken \t \r\n Type="" \t \r\n Property="" \n /] ... [CT ... The is the RegularExpression that I am currently using: (\[CustomToken).*?(\/\]) .NET API Regex.Matches(string input, string pattern) Thanks for your suggestion.

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  • Strange behavior of std::cout &operator<<...

    - by themoondothshine
    Hey ppl, I came across something weird today, and I was wondering if any of you here could explain what's happening... Here's a sample: #include <iostream> #include <cassert> using namespace std; #define REQUIRE_STRING(s) assert(s != 0) #define REQUIRE_STRING_LEN(s, n) assert(s != 0 || n == 0) class String { public: String(const char *str, size_t len) : __data(__construct(str, len)), __len(len) {} ~String() { __destroy(__data); } const char *toString() const { return const_cast<const char *>(__data); } String &toUpper() { REQUIRE_STRING_LEN(__data, __len); char *it = __data; while(it < __data + __len) { if(*it >= 'a' && *it <= 'z') *it -= 32; ++it; } return *this; } String &toLower() { REQUIRE_STRING_LEN(__data, __len); char *it = __data; while(it < __data + __len) { if(*it >= 'A' && *it <= 'Z') *it += 32; ++it; } return *this; } private: char *__data; size_t __len; protected: static char *__construct(const char *str, size_t len) { REQUIRE_STRING_LEN(str, len); char *data = new char[len]; std::copy(str, str + len, data); return data; } static void __destroy(char *data) { REQUIRE_STRING(data); delete[] data; } }; int main() { String s("Hello world!", __builtin_strlen("Hello world!")); cout << s.toLower().toString() << endl; cout << s.toUpper().toString() << endl; cout << s.toLower().toString() << endl << s.toUpper().toString() << endl; return 0; } Now, I had expected the output to be: hello world! HELLO WORLD! hello world! HELLO WORLD! but instead I got this: hello world! HELLO WORLD! hello world! hello world! I can't really understand why the second toUpper didn't have any effect.

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  • How to write a custom predicate for multi_index_containder with composite_key?

    - by Titan
    I googled and searched in the boost's man, but didn't find any examples. May be it's a stupid question...anyway. So we have the famous phonebook from the man: typedef multi_index_container< phonebook_entry, indexed_by< ordered_non_unique< composite_key< phonebook_entry, member<phonebook_entry,std::string,&phonebook_entry::family_name>, member<phonebook_entry,std::string,&phonebook_entry::given_name> >, composite_key_compare< std::less<std::string>, // family names sorted as by default std::greater<std::string> // given names reversed > >, ordered_unique< member<phonebook_entry,std::string,&phonebook_entry::phone_number> > > > phonebook; phonebook pb; ... // look for all Whites std::pair<phonebook::iterator,phonebook::iterator> p= pb.equal_range(boost::make_tuple("White"), my_custom_comp()); How should my_custom_comp() look like? I mean it's clear for me then it takes boost::multi_index::composite_key_result<CompositeKey> as an argumen (due to compilation errors :) ), but what is CompositeKey in that particular case? struct my_custom_comp { bool operator()( ?? boost::multi_index::composite_key_result<CompositeKey> ?? ) const { return blah_blah_blah; } }; Thanks in advance.

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  • Does not contain a definition

    - by JB
    public void button2_Click(object sender, System.EventArgs e) { string text = textBox1.Text; Mainform = this; this.Hide(); GetSchedule myScheduleFinder = new GetSchedule(); string result = myScheduleFinder.GetDataFromNumber(text);// says there is no definition if (!string.IsNullOrEmpty(result)) { MessageBox.Show(result); } else { MessageBox.Show("Enter A Valid ID Number!"); } } says it does not contain definition for it but on my GetSchedule .cs file i have it defined public string GetDataFromNumber(string ID)//defined here { foreach (IDnumber IDCandidateMatch in IDnumbers) { if (IDCandidateMatch.ID == ID) { StringBuilder myData = new StringBuilder(); myData.AppendLine(IDCandidateMatch.Name); myData.AppendLine(": "); myData.AppendLine(IDCandidateMatch.ID); myData.AppendLine(IDCandidateMatch.year); myData.AppendLine(IDCandidateMatch.class1); myData.AppendLine(IDCandidateMatch.class2); myData.AppendLine(IDCandidateMatch.class3); myData.AppendLine(IDCandidateMatch.class4); //return myData; return myData.ToString(); } } return ""; } } } }

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  • ASP.NET MVC - How do I implement validation when using Data Repositories? (Visual Basic)

    - by rockinthesixstring
    I've built a UserRepository interface to communicate with my LINQ to SQL Data layer, but I'm trying to figure out how to implement validation. Here is what my AddUser subroutine looks like Public Sub AddUser(ByVal about As String, ByVal birthdate As DateTime, ByVal openid As String, ByVal regionid As Integer, ByVal website As String) Implements IUserRepository.AddUser Dim user = New User user.About = about user.BirthDate = birthdate user.LastSeen = DateTime.Now user.MemberSince = DateTime.Now user.OpenID = openid user.RegionID = regionid user.UserName = String.Empty user.WebSite = website dc.Users.InsertOnSubmit(user) dc.SubmitChanges() End Sub And then my controller will simply call AddUser(...) But I haven't the foggiest idea on how to implement both client side and server side validation on this. (I think I would prefer to use jQuery AJAX and do all of the validation on the server, but I'm totally open to opinions)

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  • How to handle server-client requests

    - by Layne
    Currently I'm working on a Server-Client system which will be the backbone of my application. I have to find the best way to send requests and handle them on the server-side. The server-side should be able to handle requests like this one: getPortfolio -i 2 -d all In an old project I decided to send such a request as string and the server application had to look up the first part of the string ("getPortfolio"). Afterwards the server application had to find the correct method in a map which linked the methods with the the first part of the string ("getPortfolio"). The second part ("-i 2 -d all") got passed as parameter and the method itself had to handle this string/parameter. I doubt that this is the best solution in order to handle many different requests. Rgds Layne

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  • Getting an updated location in Android

    - by jul
    Hi, I'm using the code shown below to get an updated value for location every time a button is clicked. When my activity is resumed I get an update every second, so that when I call getLastKnownLocation I expect to have a location that have been updated in the last second. Is that the correct way to do that? I would expect the onLocationChanged event to be triggered every time I execute a 'geo fix' command (or max after 1s since I request update every 1s), but it's only triggered the first time. Why? Any help/suggestion welcome! Thanks package org.digitalfarm.atable; ... public class Atable extends Activity { private Button mSearchButton; private TextView mytext; private LocationManager locationManager; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mSearchButton = (Button)this.findViewById(R.id.button); mytext = (TextView) findViewById(R.id.dude); locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE); final Criteria criteria = new Criteria(); criteria.setAccuracy(Criteria.ACCURACY_FINE); mSearchButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { String provider = locationManager.getBestProvider(criteria, true); Location location = locationManager.getLastKnownLocation(provider); } }); } //Start a location listener LocationListener onLocationChange=new LocationListener() { public void onLocationChanged(Location loc) { //sets and displays the lat/long when a location is provided String latlong = "Lat: " + loc.getLatitude() + " Long: " + loc.getLongitude(); mytext.setText(latlong); } public void onProviderDisabled(String provider) { // required for interface, not used } public void onProviderEnabled(String provider) { // required for interface, not used } public void onStatusChanged(String provider, int status, Bundle extras) { // required for interface, not used } }; //pauses listener while app is inactive @Override public void onPause() { super.onPause(); locationManager.removeUpdates(onLocationChange); } //reactivates listener when app is resumed @Override public void onResume() { super.onResume(); locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,1000,100.0f,onLocationChange); } }

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  • Uncaught SyntaxError: Unexpected token var

    - by Bob R
    I have an error Uncaught SyntaxError: Unexpected token var displayed between (1) and (2) its a very odd error and it doesn't make sense at all. if ($hiddenimage.length==0){ //if this is the first time moving over or clicking on the anchor link var $hiddenimage=$('<img src="'+this.href+'" />').appendTo($hiddenimagediv) //populate hidden div with enlarged image $hiddenimage.bind('loadevt', function(e){ //when enlarged image has fully loaded loadarea.empty().append($.thumbnailviewer2.buildimage($, $anchor, s, options) (1) - var $targetimage=$.thumbnailviewer2.buildimage($, $anchor, s, options) //create reference actual enlarged image (2) - $loadarea.empty().append($targetimage) //show enlarged image $.thumbnailviewer2.showimage($targetimage, s) })

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  • Count number of occurrences of a pattern in a file (even on same line)

    - by jrdioko
    When searching for number of occurrences of a string in a file, I generally use: grep pattern file | wc -l However, this only finds one occurrence per line, because of the way grep works. How can I search for the number of times a string appears in a file, regardless of whether they are on the same or different lines? Also, what if I'm searching for a regex pattern, not a simple string? How can I count those, or, even better, print each match on a new line?

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  • how to find datakeys in oncheckedchanged event ?

    - by subodh
    <asp:Panel ID="pnlFocusAreaPanel" runat="server" GroupingText="Focus Area" Width="800"> <table cellspacing="0" cellpadding="0" width="750"> <tr> <td> <asp:GridView ID="dgFocusAreaDetails" runat="server" Width="100%" CssClass="dgStyle" AutoGenerateColumns="False" BorderColor="Silver" BorderWidth="1px" CellPadding="0" ShowHeader="False" OnSelectedIndexChanged="dgFocusAreaDetails_SelectedIndexChanged" DataKeyNames="PK_ID"> <FooterStyle Font-Underline="True" HorizontalAlign="Center" VerticalAlign="Middle"> </FooterStyle> <Columns> <asp:TemplateField HeaderText="Focus Area" HeaderStyle-BackColor="Silver"> <ItemStyle Width="90%" /> <ItemTemplate> <asp:Label runat="server" ID="lblFocusArea" Text='<%# DataBinder.Eval(Container.DataItem, "FOCUS_AREA_NAME").ToString()%>'> </asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Is Current Valid" HeaderStyle-BackColor="Silver"> <ItemStyle Width="10%" HorizontalAlign="Center" /> <ItemTemplate> <asp:CheckBox ID="chkFocusArea" runat="server" OnCheckedChanged="OnCheckChangedEvent" AutoPostBack="true" /> </ItemTemplate> </asp:TemplateField> </Columns> </asp:GridView> </td> </tr> <tr> <td align="left"> <asp:TextBox ID="txtFocusArea" runat="server" Width="300px" CausesValidation="true" CssClass="txtStyle" ValidationGroup="focusArea"> </asp:TextBox> <cc1:TextBoxWatermarkExtender ID="txtFocusAreaWaterMark" runat="server" TargetControlID="txtFocusArea" WatermarkText="Add Focus Area" WatermarkCssClass="WaterMarkStyle"> </cc1:TextBoxWatermarkExtender> <asp:Button ID="btnAddFocusArea" runat="server" Text="AddFocusArea" CssClass="btnStyle" OnClick="btnAddFocusArea_Click" CausesValidation="true" ValidationGroup="focusArea" /> <asp:RequiredFieldValidator ID="reqtxtFocusArea" runat="server" ControlToValidate="txtFocusArea" ErrorMessage="Please enter focus area" Display="Dynamic" ValidationGroup="focusArea"> </asp:RequiredFieldValidator> <asp:RegularExpressionValidator ID="regexFocusArea" runat="server" ErrorMessage="Invalid characters(<,>,#)" ControlToValidate="txtFocusArea" ValidationExpression="^([^&lt;#&gt;]*)$" ValidationGroup="focusArea" Display="Dynamic" SetFocusOnError="true"> </asp:RegularExpressionValidator> </td> </tr> </table> </asp:Panel> and in code behind protected void btnAddFocusArea_Click(object sender, EventArgs e) { string strFocusArea = txtFocusArea.Text; OleDbConnection myConnection = new OleDbConnection(ConfigurationSettings.AppSettings["SQLConnectionString"]); if (strFocusArea == string.Empty || strFocusArea == txtFocusAreaWaterMark.WatermarkText) { lblError.Text = "Focus area is not entered"; } else { string insertQuery = "INSERT INTO LK_CODECAT_FOCUS_AREA(FOCUS_AREA_NAME,FK_ADDED_BY,ADDED_ON) "+ " VALUES('" + strFocusArea + "', "+Session["UserID"] +", GETDATE())"; try { myConnection.Open(); OleDbCommand myCommandToInsert = new OleDbCommand(insertQuery, myConnection); myCommandToInsert.ExecuteNonQuery(); } catch(Exception exc) { ExceptionLogger.LogException(exc); } finally { if (myConnection != null) { myConnection.Close(); } } PopulateFocusArea(); } txtFocusArea.Text = txtFocusAreaWaterMark.WatermarkText; } private void PopulateFocusArea() { OleDbConnection myConnection = new OleDbConnection(ConfigurationSettings.AppSettings["SQLConnectionString"]); string selectQuery = "SELECT PK_ID, FOCUS_AREA_NAME, IS_CURRENT_FOCUS FROM LK_CODECAT_FOCUS_AREA LKCFA ORDER BY FOCUS_AREA_NAME"; if (Session["RoleID"].ToString() == "1" || ((Session["WorkID"].ToString() != "9") || (Session["WorkID2"].ToString() != "9") || (Session["WorkID3"].ToString() != "9"))) { try { myConnection.Open(); OleDbCommand myCommandFocusArea = new OleDbCommand(selectQuery, myConnection); OleDbDataAdapter myAdapter = new OleDbDataAdapter(myCommandFocusArea); DataSet ds = new DataSet(); myAdapter.Fill(ds); dgFocusAreaDetails.DataSource = ds; dgFocusAreaDetails.ShowHeader = true; dgFocusAreaDetails.DataBind(); } catch (Exception exc) { ExceptionLogger.LogException(exc); } finally { if (myConnection != null) { myConnection.Close(); } } } } protected void dgFocusAreaDetails_SelectedIndexChanged(object sender, EventArgs e) { string selectedCategory = dgFocusAreaDetails.SelectedRow.Cells[1].Text; int index = dgFocusAreaDetails.SelectedIndex; lblError.Text = dgFocusAreaDetails.DataKeys[index].Value.ToString(); } public void OnCheckChangedEvent(object sender, EventArgs e) { CheckBox chk = (CheckBox)sender; string chkfocusarea = ((Control)chk).ID; //string focusAreaDetails = dgFocusAreaDetails.SelectedRow.Cells[0].Text; int index =Convert.ToInt32(dgFocusAreaDetails.SelectedIndex); if (chk.Checked) { string updateQuery = "UPDATE [LK_CODECAT_FOCUS_AREA] SET [IS_CURRENT_FOCUS] = 1 WHERE PK_ID = " +Convert.ToInt32( dgFocusAreaDetails.DataKeys[index].Value)+" "; } else { lblError.Text = "unchecked"; } } i want to know how i find the datakeyvalue on checked event.

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  • Dealing with &rest-parameters in common lisp

    - by Patrick
    I want define a functions that accepts &rest - parameters and delegates them to another function. (html "blah" "foo" baz) = "blahfoobaz" I did not find a better way than this one: (defun html (&rest values) (concatenate 'string "" (reduce #'(lambda(a b) (concatenate 'string a b)) values :initial-value "") "")) But this looks somewhat glumbsy to me, since line 4 does no more than concatenating the &rest parameter "values". I tried (concatenate 'string "" (values-list values) "") but this does not seem to work (SBCL). Could someone give me an advice? Kind regards

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  • How to open connection to local network path protected by password in smart way? (Whith C#)

    - by lfx
    Hi, I developing program witch have to write some data in file whom are stored in network computer witch are protected by password. Now I'm doing this way - open connection with cmd then write data. static bool ConnectToSrv() { String myUser = "domain.local\\user"; String myPass = "pwd"; String cmdString = "net use \\\\otherPC\\folder\\ /user:" + myUser + " " + myPass; try { ManagementClass processClass = new ManagementClass("Win32_Process"); object[] methodArgs = { cmdString, null, null, 0 }; object result = processClass.InvokeMethod("Create", methodArgs); return true; } catch (System.Exception error) { return false; } } public void writeDate(string data){ } I believe there must by better way. I mean the .NET way. Does anybody know how to do it? :) Thanks

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  • jsf annotations

    - by Andrew Bucknell
    I've created an address bean and I want to use it twice - once for street address and once for mailing address. I can achieve this using faces config as per the below, but I'm wondering if I can do this via annotations. e.g. put @ManagedBean(name="StreetAddress") and @ManagedBean(name="MailingAddress") on the same class? I feel like I am missing something obvious here but I'm not sure what. <managed-bean> <managed-bean-name>MailingAddress</managed-bean-name> <managed-bean-class>com.leetb.jsf_ex1.model.AddressBean</managed-bean-class> <managed-bean-scope>session</managed-bean-scope> <map-entries/> </managed-bean> <managed-bean> <managed-bean-name>StreetAddress</managed-bean-name> <managed-bean-class>com.leetb.jsf_ex1.model.AddressBean</managed-bean-class> <managed-bean-scope>session</managed-bean-scope> <map-entries/> </managed-bean> public class AddressBean { private String line_one; private String line_two; private String suburb; private String state; private String postcode; /* getters and setters snipped */ }

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  • If Else Conditionals within Function in JavaScript

    - by Antoine-Laurent Lavoisier
    I'm having issues with conditionals. I want to return the index where pattern starts in string (or -1 if not found). The search is to be case sensitive if the 3rd parameter is true otherwise it is case insensitive. Examples index("abAB12","AB",true) returns 2 but index("abAB12","AB",false) returns 0 index("abAB12","BA",true) returns -1 and index("abAB12","BA",false) returns 1 Any idea how I can accomplish this? This is my code so far var s = "abAB12" var p = "AB" var cs = true function index(string, pattern, caseSensitive) { if (pattern) { var found = false; if (caseSensitive = false) { if (string.indexOf(pattern.) >= 0) { found = true; } return (found); else { return (""); } } else if (caseSensitive = true) { if (string.toLowerCase().indexOf(pattern.toLowerCase()) >= 0) { found = true; } return (found); } else { return (""); } } } alert(index(s, p, cs)); Fiddle at http://jsfiddle.net/AfDFb/1/

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  • Retrieve a static variable using its name dynamically using reflection

    - by user2538438
    How to retrieve a static variable using its name dynamically using Java reflection? If I have class containing some variables: public class myClass { string [][] cfg1= {{"01"},{"02"},{"81"},{"82"}}; string [][]cfg2= {{"c01"},{"c02"},{"c81"},{"c82"}}; string [][] cfg3= {{"d01"},{"d02"},{"d81"}{"d82"}}; int cfg11 = 5; int cfg22 = 10; int cfg33 = 15; } And in another class I want variable name is input from user: class test { Scanner in = new Scanner(System.in); String userInput = in.nextLine(); // get variable from class myClass that has the same name as userInput System.out.println("variable name " + // correct variable from class) } Using reflection. Any help please?

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  • ResXResourceWriter Chops off end of file

    - by Aaron Salazar
    I'm trying to create a .resx file from a dictionary of strings. Luckily the .Net framework has a ResXResourceWriter class. The only problem is that when I create the file using the code below, the last few lines of my generated resx file are missing. I checked my Dictionary and it contains all the string pairs that I expect. public void ExportToResx(Dictionary<string,string> resourceDictionary, string fileName) { var writer = new ResXResourceWriter(fileName); foreach (var resource in resourceDictionary) { writer.AddResource(resource.Key, resource.Value); } } Unfortunately, it is a little difficult to show the entire resx file since it has 2198 (should have 2222) lines but here is the last little bit: ... 2195 <data name="LangAlign_ReportIssue" xml:space="preserve"> 2196 <value>Report an Issue</value> 2197 </data> 2198 <data name="LangAlign_Return BTW, notice that the file cuts off right at the end of that "n" in "LangAlign_Return". The string should read "LangAlign_ReturnToWorkspace". The file should also end at line 2222.

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  • Linq-to-XML explicit casting in a generic method

    - by vlad
    I've looked for a similar question, but the only one that was close didn't help me in the end. I have an XML file that looks like this: <Fields> <Field name="abc" value="2011-01-01" /> <Field name="xyz" value="" /> <Field name="tuv" value="123.456" /> </Fields> I'm trying to use Linq-to-XML to get the values from these fields. The values can be of type Decimal, DateTime, String and Int32. I was able to get the fields one by one using a relatively simple query. For example, I'm getting the 'value' from the field with the name 'abc' using the following: private DateTime GetValueFromAttribute(IEnumerable<XElement> fields, String attName) { return (from field in fields where field.Attribute("name").Value == "abc" select (DateTime)field.Attribute("value")).FirstOrDefault() } this is placed in a separate function that simply returns this value, and everything works fine (since I know that there is only one element with the name attribute set to 'abc'). however, since I have to do this for decimals and integers and dates, I was wondering if I can make a generic function that works in all cases. this is where I got stuck. here's what I have so far: private T GetValueFromAttribute<T>(IEnumerable<XElement> fields, String attName) { return (from field in fields where field.Attribute("name").Value == attName select (T)field.Attribute("value").Value).FirstOrDefault(); } this doesn't compile because it doesn't know how to convert from String to T. I tried boxing and unboxing (i.e. select (T) (Object) field.Attribute("value").Value but that throws a runtime Specified cast is not valid exception as it's trying to convert the String to a DateTime, for instance. Is this possible in a generic function? can I put a constraint on the generic function to make it work? or do I have to have separate functions to take advantage of Linq-to-XML's explicit cast operators?

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  • Can I refer to NSDictionary items numerically?

    - by cannyboy
    I'm trying to set up a UITableView which acts as a form. Each cell has within it a UILabel and a UITextField, so one cell is: Name <enter name> ^ ^ UILabel UITextField Now, I'm trying to populate the UILabel and the UITextField from a NSDictionary (from a plist), where it's organized like so: Root Type Value Name String Address String City String etc But in order to get the right labels and textfields in the cellForRowAtIndexPath method, I would have to refer to the Dictionary numerically. Is there any way to do that?

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  • Covariance and contravariance real world example

    - by Sir Psycho
    I'm having a little trouble understaing how I would use covariance and contravariance in the real world. So far, the only example's I've seen have been the same old array example. object[] objectArray = new string[] { "string 1", "string 2" }; It would be nice to see an example that would allow me to use it during my development if I could see it being used elsewhere. Can anyone point me to some useful resources?

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  • Benchmark of Java Try/Catch Block

    - by hectorg87
    I know that going into a catch block has some significance cost when executing a program, however, I was wondering if entering a try{} block also had any impact so I started looking for an answer in google with many opinions, but no benchmarking at all. Some answers I found were: Java try/catch performance, is it recommended to keep what is inside the try clause to a minimum? Try Catch Performance Java Java try catch blocks However they didn't answer my question with facts, so I decided to try it for myself. Here's what I did. I have a csv file with this format: host;ip;number;date;status;email;uid;name;lastname;promo_code; where everything after status is optional and will not even have the corresponding ; , so when parsing a validation has to be done to see if the value is there, here's where the try/catch issue came to my mind. The current code that in inherited in my company does this: StringTokenizer st=new StringTokenizer(line,";"); String host = st.nextToken(); String ip = st.nextToken(); String number = st.nextToken(); String date = st.nextToken(); String status = st.nextToken(); String email = ""; try{ email = st.nextToken(); }catch(NoSuchElementException e){ email = ""; } and it repeats what it's done for email with uid, name, lastname and promo_code. and I changed everything to: if(st.hasMoreTokens()){ email = st.nextToken(); } and in fact it performs faster. When parsing a file that doesn't have the optional columns. Here are the average times: --- Trying:122 milliseconds --- Checking:33 milliseconds however, here's what confused me and the reason I'm asking: When running the example with values for the optional columns in all 8000 lines of the CSV, the if() version still performs better than the try/catch version, so my question is Does really the try block does not have any performance impact on my code? The average times for this example are: --- Trying:105 milliseconds --- Checking:43 milliseconds Can somebody explain what's going on here? Thanks a lot

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  • Converting my lightweight MySQL DB wrapper into MySQLi. Pesky Problems

    - by Chaplin
    Here is the original code: http://pastebin.com/DNxtmApY. I'm not that interested in prepared statements at the moment, I just want this wrapper updating to MySQLi so once MySQL becomes depreciated I haven't got to update a billion websites. Here is my attempt at converting to MySQLi. <? $database_host = "127.0.0.1"; $database_user = "user"; $database_pass = "pass"; $database_name = "name"; $db = new database($database_host, $database_user, $database_pass, $database_name); class database { var $link, $result; function database($host, $user, $pass, $db) { $this->link = mysqli_connect($host, $user, $pass, $db) or $this->error(); mysqli_select_db($db, $this->link) or $this->error(); } function query($query) { $this->result = mysqli_query($query, $this->link) or $this->error(); $this->_query_count++; return $this->result; } function countRows($result = "") { if ( empty( $result ) ) $result = $this->result; return mysqli_num_rows($result); } function fetch($result = "") { if ( empty( $result ) ) $result = $this->result; return mysqli_fetch_array($result); } function fetch_num($result = "") { if ( empty( $result ) ) $result = $this->result; return mysqli_fetch_array($result, mysqli_NUM); } function fetch_assoc($result = "") { if ( empty( $result ) ) $result = $this->result; return mysqli_fetch_array($result, mysqli_ASSOC); } function escape($str) { return mysqli_real_escape_string($str); } function error() { if ( $_GET["debug"] == 1 ){ die(mysqi_error()); } else { echo "Error in db code"; } } } function sanitize($data) { //apply stripslashes if magic_quotes_gpc is enabled if(get_magic_quotes_gpc()) $data = stripslashes($data); // a mysqli connection is required before using this function $data = trim(mysqli_real_escape_string($data)); return $data; } However it chucks all sorts of errors: Warning: mysql_query(): Access denied for user 'www-data'@'localhost' (using password: NO) in /home/count/Workspace/lib/classes/user.php on line 7 Warning: mysql_query(): A link to the server could not be established in /home/count/Workspace/lib/classes/user.php on line 7 Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in /home/count/Workspace/lib/classes/user.php on line 8 Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, object given in /home/count/Workspace/lib/classes/database.php on line 31

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  • How to specify multiple values in where with AR query interface in rails3

    - by wkhatch
    Per section 2.2 of rails guide on Active Record query interface here: which seems to indicate that I can pass a string specifying the condition(s), then an array of values that should be substituted at some point while the arel is being built. So I've got a statement that generates my conditions string, which can be a varying number of attributes chained together with either AND or OR between them, and I pass in an array as the second arg to the where method, and I get: ActiveRecord::PreparedStatementInvalid: wrong number of bind variables (1 for 5) which leads me to believe I'm doing this incorrectly. However, I'm not finding anything on how to do it correctly. To restate the problem another way, I need to pass in a string to the where method such as "table.attribute = ? AND table.attribute1 = ? OR table.attribute1 = ?" with an unknown number of these conditions anded or ored together, and then pass something, what I thought would be an array as the second argument that would be used to substitute the values in the first argument conditions string. Is this the correct approach, or, I'm just missing some other huge concept somewhere and I'm coming at this all wrong? I'd think that somehow, this has to be possible, short of just generating a raw sql string.

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