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  • ASP.MVC 2 Model Data Persistance

    - by toccig
    I'm and MVC1 programmer, new to the MVC2. The data will not persist to the database in an edit scenario. Create works fine. Controller: // // POST: /Attendee/Edit/5 [Authorize(Roles = "Admin")] [AcceptVerbs(HttpVerbs.Post)] public ActionResult Edit(Attendee attendee) { if (ModelState.IsValid) { UpdateModel(attendee, "Attendee"); repository.Save(); return RedirectToAction("Details", attendee); } else { return View(attendee); } } Model: [MetadataType(typeof(Attendee_Validation))] public partial class Attendee { } public class Attendee_Validation { [HiddenInput(DisplayValue = false)] public int attendee_id { get; set; } [HiddenInput(DisplayValue = false)] public int attendee_pin { get; set; } [Required(ErrorMessage = "* required")] [StringLength(50, ErrorMessage = "* Must be under 50 characters")] public string attendee_fname { get; set; } [StringLength(50, ErrorMessage = "* Must be under 50 characters")] public string attendee_mname { get; set; } } I tried to add [Bind(Exclude="attendee_id")] above the Class declaration, but then the value of the attendee_id attribute is set to '0'. View (Strongly-Typed): <% using (Html.BeginForm()) {%> ... <%=Html.Hidden("attendee_id", Model.attendee_id) %> ... <%=Html.SubmitButton("btnSubmit", "Save") %> <% } %> Basically, the repository.Save(); function seems to do nothing. I imagine it has something to do with a primary key constraint violation. But I'm not getting any errors from SQL Server. The application appears to runs fine, but the data is never persisted to the Database.

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  • "Function object is unsubscriptable" in basic integer to string mapping function

    - by IanWhalen
    I'm trying to write a function to return the word string of any number less than 1000. Everytime I run my code at the interactive prompt it appears to work without issue but when I try to import wordify and run it with a test number higher than 20 it fails as "TypeError: 'function' object is unsubscriptable". Based on the error message, it seems the issue is when it tries to index numString (for example trying to extract the number 4 out of the test case of n = 24) and the compiler thinks numString is a function instead of a string. since the first line of the function is me defining numString as a string of the variable n, I'm not really sure why that is. Any help in getting around this error, or even just help in explaining why I'm seeing it, would be awesome. def wordify(n): # Convert n to a string to parse out ones, tens and hundreds later. numString = str(n) # N less than 20 is hard-coded. if n < 21: return numToWordMap(n) # N between 21 and 99 parses ones and tens then concatenates. elif n < 100: onesNum = numString[-1] ones = numToWordMap(int(onesNum)) tensNum = numString[-2] tens = numToWordMap(int(tensNum)*10) return tens+ones else: # TODO pass def numToWordMap(num): mapping = { 0:"", 1:"one", 2:"two", 3:"three", 4:"four", 5:"five", 6:"six", 7:"seven", 8:"eight", 9:"nine", 10:"ten", 11:"eleven", 12:"twelve", 13:"thirteen", 14:"fourteen", 15:"fifteen", 16:"sixteen", 17:"seventeen", 18:"eighteen", 19:"nineteen", 20:"twenty", 30:"thirty", 40:"fourty", 50:"fifty", 60:"sixty", 70:"seventy", 80:"eighty", 90:"ninety", 100:"onehundred", 200:"twohundred", 300:"threehundred", 400:"fourhundred", 500:"fivehundred", 600:"sixhundred", 700:"sevenhundred", 800:"eighthundred", 900:"ninehundred", } return mapping[num] if __name__ == '__main__': pass

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  • Casting Type array to Generic array?

    - by George R
    The short version of the question - why can't I do this? I'm restricted to .NET 3.5. T[] genericArray; // Obviously T should be float! genericArray = new T[3]{ 1.0f, 2.0f, 0.0f }; // Can't do this either, why the hell not genericArray = new float[3]{ 1.0f, 2.0f, 0.0f }; Longer version - I'm working with the Unity engine here, although that's not important. What is - I'm trying to throw conversion between its fixed Vector2 (2 floats) and Vector3 (3 floats) and my generic Vector< class. I can't cast types directly to a generic array. using UnityEngine; public struct Vector { private readonly T[] _axes; #region Constructors public Vector(int axisCount) { this._axes = new T[axisCount]; } public Vector(T x, T y) { this._axes = new T[2] { x, y }; } public Vector(T x, T y, T z) { this._axes = new T[3]{x, y, z}; } public Vector(Vector2 vector2) { // This doesn't work this._axes = new T[2] { vector2.x, vector2.y }; } public Vector(Vector3 vector3) { // Nor does this this._axes = new T[3] { vector3.x, vector3.y, vector3.z }; } #endregion #region Properties public T this[int i] { get { return _axes[i]; } set { _axes[i] = value; } } public T X { get { return _axes[0];} set { _axes[0] = value; } } public T Y { get { return _axes[1]; } set { _axes[1] = value; } } public T Z { get { return this._axes.Length (Vector2 vector2) { Vector vector = new Vector(vector2); return vector; } public static explicit operator Vector(Vector3 vector3) { Vector vector = new Vector(vector3); return vector; } #endregion }

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  • Unreleased Resource: Streams

    - by Vibhas
    Hi freinds i am getting a warning in the fortify report for the following code: if (null != serverSocket) { OutputStream socketOutPutStream = serverSocket .getOutputStream(); if (null != socketOutPutStream) { oos = new ObjectOutputStream(socketOutPutStream); if (null != oos) { int c; log.info("i am in Step 3 ooss " + oos); while ((c = mergedIS.read()) != -1) { oos.writeByte(c); } } log.info("i am in Step 4 "); } } in the catch block i have mentioned : catch (UnknownHostException e) { //catch exception Vibhas added log.info("UnknownHostException occured"); } catch (IOException e) { //catch exception Vibhas added log.info("IOException occured"); } catch (Exception e) { //catch exception //log.info("error occured in copyFile in utils-->"+e.getMessage()+"file name is-->"+destiFileName); }finally{ if (null != oos){ oos.flush(); oos.close(); } catch (Exception e) { //catch exception } } Warning which i am getting in the fortify report is: Abstract: The function copyFile() in ODCUtil.java sometimes fails to release a system resource allocated by getOutputStream() on line 61. Sink: ODCUtil.java:64 oos = new ObjectOutputStream(socketOutPutStream)() 62 if (null != socketOutPutStream) { 63 64 oos = new ObjectOutputStream(socketOutPutStream); 65 if (null != oos) { 66 int c;

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  • Template trick to optimize out allocations

    - by anon
    I have: struct DoubleVec { std::vector<double> data; }; DoubleVec operator+(const DoubleVec& lhs, const DoubleVec& rhs) { DoubleVec ans(lhs.size()); for(int i = 0; i < lhs.size(); ++i) { ans[i] = lhs[i]] + rhs[i]; // assume lhs.size() == rhs.size() } return ans; } DoubleVec someFunc(DoubleVec a, DoubleVec b, DoubleVec c, DoubleVec d) { DoubleVec ans = a + b + c + d; } Now, in the above, the "a + b + c + d" will cause the creation of 3 temporary DoubleVec's -- is there a way to optimize this away with some type of template magic ... i.e. to optimize it down to something equivalent to: DoubleVec ans(a.size()); for(int i = 0; i < ans.size(); i++) ans[i] = a[i] + b[i] + c[i] + d[i]; You can assume all DoubleVec's have the same # of elements. The high level idea is to have do some type of templateied magic on "+", which "delays the computation" until the =, at which point it looks into itself, goes hmm ... I'm just adding thes numbers, and syntheizes a[i] + b[i] + c[i] + d[i] ... instead of all the temporaries. Thanks!

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  • passing data from an activity to an listactivity or listview

    - by wicked14
    need help on passing data from an activity to an listactivity or listview for an android app. im having problems on passing data to a listview. what the app do is from addact class the user can input things to do and in the viewact class this will display the activies add by the user in listview public class addact extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.newact); Button btn1 = (Button)findViewById(R.id.btnsave); final EditText et1 = (EditText)findViewById(R.id.etactivity); btn1.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { Intent it = new Intent(addact.this, viewact.class); it.putExtra("thekey", et1.getText().toString()); startActivity(it); } }); } } public class viewact extends ListActivity { String addToDo =getIntent().getExtras().getString("thekey"); String[] toDoAct = new String[] {addToDo }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.viewact); setListAdapter(new ArrayAdapter<String>(this, R.layout.viewact,toDoAct)); ListView listView = getListView(); listView.setTextFilterEnabled(true); listView.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { for (int i=0; i < 2; i++) { Toast.makeText(getApplicationContext(), ((TextView) view).getText(), Toast.LENGTH_LONG).show(); } } }); } }

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  • Changing brightness in bufferedImage with DataBufferInt

    - by user2958025
    I must read some image and then I have to change brightness and contrast of this image I create main class and constructor where are panels, sliders and other stuff, I added changeListener to slider to take current value. My imagePanel is new Object of that class: public class Obrazek extends JPanel{ public static BufferedImage img = null; public Obrazek() { super(); try { img = ImageIO.read(new File("D:\\ja.jpg")); } catch (IOException e) {} } @Override public void paint(Graphics g) { g.drawImage(img, 0, 0, null); } } This is my load button private void przyciskWczytaj(java.awt.event.ActionEvent evt) { int odpowiedz = jFileChooser1.showOpenDialog(this); if (odpowiedz == jFileChooser1.APPROVE_OPTION) { File file = jFileChooser1.getSelectedFile(); try { BufferedImage im = ImageIO.read(new File(file.getAbsolutePath())); Obrazek.img = im; } catch (IOException ex) { System.out.println("Error"); } } } And now I want to create class where I will change that brightness. I have to use but I don't know how to use that thing: BufferedImage(256, 256, Bufferedmage.TYPE_INT_RGB) and to get each pixel of image I need to do something like: int rgb []=((DataBufferInt)img.getRaster().getDataBuffer()).getData(); And here I is next problem: How can I change the value of each r,g,b and show that new image on my panel

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  • Access-specifiers are not foolproof?

    - by Nawaz
    If I've a class like this, class Sample { private: int X; }; Then we cannot access X from outside, so this is illegal, Sample s; s.X = 10; // error - private access But we can make it accessible without editing the class! All we need to do is this, #define private public //note this define! class Sample { private: int X; }; //outside code Sample s; s.X = 10; //no error! Working code at ideone : http://www.ideone.com/FaGpZ That means, we can change the access-specifiers by defining such macros just before the class definition, or before #include <headerfile.h>, #define public private //make public private //or #define protected private //make protected private //or #define so on Isn't it a problem with C++ (Macros/access-specifiers/whatever)? Anyway, the point of this topic is: Using macros, we can easily violate encapsulation. Access-specifiers are not foolproof! Am I right?

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  • Get the first and last posts in a thread

    - by Grampa
    I am trying to code a forum website and I want to display a list of threads. Each thread should be accompanied by info about the first post (the "head" of the thread) as well as the last. My current database structure is the following: threads table: id - int, PK, not NULL, auto-increment name - varchar(255) posts table: id - int, PK, not NULL, auto-increment thread_id - FK for threads The tables have other fields as well, but they are not relevant for the query. I am interested in querying threads and somehow JOINing with posts so that I obtain both the first and last post for each thread in a single query (with no subqueries). So far I am able to do it using multiple queries, and I have defined the first post as being: SELECT * FROM threads t LEFT JOIN posts p ON t.id = p.thread_id ORDER BY p.id LIMIT 0, 1 The last post is pretty much the same except for ORDER BY id DESC. Now, I could select multiple threads with their first or last posts, by doing: SELECT * FROM threads t LEFT JOIN posts p ON t.id = p.thread_id ORDER BY p.id GROUP BY t.id But of course I can't get both at once, since I would need to sort both ASC and DESC at the same time. What is the solution here? Is it even possible to use a single query? Is there any way I could change the structure of my tables to facilitate this? If this is not doable, then what tips could you give me to improve the query performance in this particular situation?

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  • Call Oracle package function using Odbc from C#

    - by Paolo Tedesco
    I have a function defined inside an Oracle package: CREATE OR REPLACE PACKAGE BODY TESTUSER.TESTPKG as FUNCTION testfunc(n IN NUMBER) RETURN NUMBER as begin return n + 1; end testfunc; end testpkg; / How can I call it from C# using Odbc? I tried the following: using System; using System.Data; using System.Data.Odbc; class Program { static void Main(string[] args) { using (OdbcConnection connection = new OdbcConnection("DSN=testdb;UID=testuser;PWD=testpwd")) { connection.Open(); OdbcCommand command = new OdbcCommand("TESTUSER.TESTPKG.testfunc", connection); command.CommandType = System.Data.CommandType.StoredProcedure; command.Parameters.Add("ret", OdbcType.Int).Direction = ParameterDirection.ReturnValue; command.Parameters.Add("n", OdbcType.Int).Direction = ParameterDirection.Input; command.Parameters["n"].Value = 42; command.ExecuteNonQuery(); Console.WriteLine(command.Parameters["ret"].Value); } } } But I get an exception saying "Invalid SQL Statement". What am I doing wrong?

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  • Android 2.1 How to get Phone Numbers of contacts.

    - by Brandon Delany
    Hi, I am new to Android and have been working on an app that needs to get all of the user's contact's phone numbers. Apparently the code I have does not work with the 2.1 SDK. So far here is the code I am using: String[] projection = new String[] { Phone.NUMBER }; Cursor c = managedQuery( Phone.CONTENT_URI, projection, null, null, null ); int colIndex = -1; try { colIndex = c.getColumnIndexOrThrow( Phone.NUMBER ); } catch( Exception e ) { print( e.getMessage() ); } print( "Column Index = " + colIndex ); //count is equal to 3 for( int i = 0; i < count; i++ ){ try { print( c.getString( 2 ) ); //the 2 used to be colIndex } catch ( Exception e ) { print( e.getMessage() ); } } It seems that no matter what I pass into c.getString() it keeps telling me that I passed in -1. But I even hardcoded the 2, and it says the same thing. Any help would be much appreciated.

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  • Algorithm to pick values from set to match target value?

    - by CSharperWithJava
    I have a fixed array of constant integer values about 300 items long (Set A). The goal of the algorithm is to pick two numbers (X and Y) from this array that fit several criteria based on input R. Formal requirement: Pick values X and Y from set A such that the expression X*Y/(X+Y) is as close as possible to R. That's all there is to it. I need a simple algorithm that will do that. Additional info: The Set A can be ordered or stored in any way, it will be hard coded eventually. Also, with a little bit of math, it can be shown that the best Y for a given X is the closest value in Set A to the expression X*R/(X-R). Also, X and Y will always be greater than R From this, I get a simple iterative algorithm that works ok: int minX = 100000000; int minY = 100000000; foreach X in A if(X<=R) continue; else Y=X*R/(X-R) Y=FindNearestIn(A, Y);//do search to find closest useable Y value in A if( X*Y/(X+Y) < minX*minY/(minX+minY) ) then minX = X; minY = Y; end end end I'm looking for a slightly more elegant approach than this brute force method. Suggestions?

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  • How to convert a list object to bigdecimal in prepared statement?

    - by user1103504
    I am using prepared statement for bulk insertion of records. Iam iterating a list which contains values and their dataTypes differ. One of the data type is BigDecimal and when i try to set calling preparedstatement, it is throwing null pointer exception. My code int count = 1; for (int j = 0; j < list.size(); j++) { if(list.get(j) instanceof Timestamp) { ps.setTimestamp(count, (Timestamp) list.get(j)); } else if(list.get(j) instanceof java.lang.Character) { ps.setString(count, String.valueOf(list.get(j))); } else if(list.get(j) instanceof java.math.BigDecimal) { ps.setBigDecimal(count, (java.math.BigDecimal)list.get(j)); } else { ps.setObject(count, list.get(j)); } count++; } I tried 2 ways to convert, casting the object and tried to create a new object of type BigDecimal ps.setBigDecimal(count, new BigDecimal(list.get(j).toString)); both donot solve my problem. It is throwing null pointer exception. help is appreciated. Thanks

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  • performing more than one Where in query return null!!! why? how to fix this?

    - by Sadegh
    hi, i have wrote a method that filters output with provided query and return it. when one Where excuted; it return correct output but when more than one Where excuted; output is null and Exception occured with message "Enumeration yielded no results". why? how i can fix it? public IQueryable<SearchResult> PerformSearch(string query, int skip = 0, int take = 5) { if (!string.IsNullOrEmpty(query)) { var queryList = query.Split('+').ToList(); var results = GENERATERESULTS(); string key; foreach (string _q in queryList) { if (_q.StartsWith("(") && _q.EndsWith(")")) { key = _q.Replace("(", "").Replace(")", ""); results = results.Where(q => q.Title.Contains(key, StringComparison.CurrentCultureIgnoreCase)); } else if (_q.StartsWith("\"") && _q.EndsWith("\"")) { key = _q.Replace("\"", "").Replace("\"", ""); results = results.Where(q => q.Title.Contains(key, StringComparison.CurrentCulture)); } else if (_q.StartsWith("-(") && _q.EndsWith(")")) { key = _q.Replace("-(", "").Replace(")", ""); results = results.Where(q=> !q.Title.Contains(key, StringComparison.CurrentCultureIgnoreCase)); } else { key = _q; results = results.Where(q => q.Title.Contains(key, StringComparison.CurrentCulture)); } } this._Count = results.Count(); results = results.Skip(skip).Take(take); this._EndOn = DateTime.Now; this.ExecutionTime(); return results; } else return null; } thanks in advance ;)

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  • returning reference to a vector from a method and using its public members

    - by memC
    dear experts, I have a vector t_vec that stores references to instances of class Too. The code is shown below. In the main , I have a vector t_vec_2 which has the same memory address as B::t_vec. But when I try to access t_vec_2[0].val1 it gives error val1 not declared. Could you please point out what is wrong? Also, if you know of a better way to return a vector from a method, please let me know! Thanks in advance. class Too { public: Too(); ~Too(){}; int val1; }; Too::Too(){ val1 = 10; }; class B { public: vector<Too*> t_vec; Too* t1; vector<Too*>& get_tvec(); B(){t1 = new Too();}; ~B(){delete t1;}; }; vector<Too*>& B::get_tvec(){ t_vec.push_back(t1); return t_vec; } int main(){ B b; b = B(); vector<Too*>& t_vec_2 = b.get_tvec(); // Getting error std::cout << "\n val1 = " << t_vec_2[0].val1; return 0; }

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  • PHP Pass Dynamic Array name to function

    - by Brad
    How do I pass an array key to a function to pull up the right key's data? // The array <?php $var['TEST1'] = Array ( 'Description' => 'This is a Description', 'Version' => '1.11', 'fields' => Array( 'ID' => array( 'type' => 'int', 'length' =>'11', 'misc' =>'auto_increment' ), 'DATA' => array( 'type' => 'varchar', ' length' => '255' ) ); $var['TEST2'] = Array ( 'Description' =? 'This is the 2nd Description', 'Version' => '2.1', 'fields' => Array( 'ID' => array( 'type' => 'int', 'length' =>'11', 'misc' =>'auto_increment' ), 'DATA' => array( 'type' => 'varchar', ' length' => '255' ) ) // The function <?php $obj = 'TEST1'; print_r($schema[$obj]); // <-- Fives me output. But calling the function doesn't. echo buildStructure($obj); /** * @TODO to add auto_inc support */ function buildStructure($obj) { $output = ''; $primaryKey = $schema["{$obj}"]['primary key']; foreach ($schema["{$obj}"]['fields'] as $name => $tag) // #### ERROR #### Invalid argument supplied for foreach() { $type = $tag['type']; $length = $tag['length']; $default = $tag['default']; $description = $tag['description']; $length = (isset($length)) ? "({$length})" : ''; $default = ($default == NULL ) ? "NULL" : $default; $output .= "`{$name}` {$type}{$length} DEFAULT {$default} COMMENT `{$DESCRIPTION}`, "; } return $output; }

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  • How can I change jtable height at runtime

    - by wniroshan
    I hava a JFrame with multiple JPanels of similar width aligned one below other. I use one of these JPanels to display a JTable which is the last JPanel of the lot. This JPanel has a JScrollpane as a child component. This is where I try to add my table dynamically. Initial height of this JScrollpane is set to 40. I designed above template using Netbeans 6.8 Now I'm trying to add the table to the JPanel. When a button is pressed below code snippet is called. The class which includes this code extends javax.swing.JFrame class. I am expecting below code would adjust table height according to the row count and display the table. SearchTable = new JTable(RowData, DisplayNames) { @Override public boolean isCellEditable(int rowIndex, int vColIndex) { return false; } }; // if row count is less than 10 then display all the rows without a scroll bar if (SearchTable.getRowCount() < 10) { pnl_tblpanel.setPreferredSize(new Dimension(625, SearchTable.getRowHeight() * (SearchTable.getRowCount() + 4))); scr_tblholder.setPreferredSize(new Dimension(625, SearchTable.getRowHeight() * (SearchTable.getRowCount() + 4))); } else {// if row count is more than 10 display first 10 rows and add a scroll bar pnl_tblpanel.setPreferredSize(new Dimension(625, SearchTable.getRowHeight() * (10 + 2))); scr_tblholder.setAutoscrolls(true); } //pnl_tblpanel.add(scr_tblholder); scr_tblholder.setViewportView(SearchTable); //pnl_tblpanel.repaint(); pnl_tblpanel.validate(); this.validate(); //this.repaint(); pnl_tblpanel.setVisible(true); this.pack(); The table displays, but the table height is not changed according to the row count. It stays its default value. I have been trying many combinations of validate and repaint but nothing worked. (More in desperation) Can anyone shed some light on this Thank you

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  • Performing measures within the execution of a c++ code every t milliseconds

    - by user506901
    Given a while loop and the function ordering as follows: int k=0; int total=100; while(k<total){ doSomething(); if(approx. t milliseconds elapsed) { measure(); } ++k; } I want to perform 'measure' every t-th milliseconds. However, since 'doSomething' can be close to the t-th millisecond from the last execution, it is acceptable to perform the measure after approximately t milliseconds elapsed from the last measure. My question is: how could this be achieved? One solution would be to set timer to zero, and measure it after every 'doSomething'. When it is withing the acceptable range, I perform measures, and reset. However, I'm not which c++ function I should use for such a task. As I can see, there are certain functions, but the debate on which one is the most appropriate is outside of my understanding. Note that some of the functions actually take into account the time taken by some other processes, but I want my timer to only measure the time of the execution of my c++ code (I hope that is clear). Another thing is the resolution of the measurements, as pointed out below. Suppose the medium option of those suggested.

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  • Generic Constraints And Type Parameters Mess

    - by Dummy01
    Hi everyone, I have the following base abstract class defined as: public abstract class BaseObject<T> : IComparable, IComparable<T>, IEquatable<T> {} I also have an interface defined as: public interface ICode<T> where T : struct { T Code { get; } } Now I want to derive a class that is inherited from BaseObject<T> and includes interface ICode<T>. I tried to define it like that: public class DerivedObject<T, U> : BaseObject<T>, ICode<U> where T : DerivedObject<T, U> where U : struct { public DerivedObject(U code) { Code = code; } // From BaseObject protected override int InstanceCompareTo(T obj) { return Code.CompareTo(obj.Code); } // From BaseObject protected override bool InstanceEquals(T obj) { return Code.Equals(obj.Code); } // From ICode U _Code; public U Code { get { return _Code; } protected set { _Code = value; } } } The only error that comes from the compiler is for Code.CompareTo(obj.Code) with the message: 'U' does not contain a definition for 'CompareTo' and no extension method 'CompareTo' accepting a first argument of type 'U' could be found. But U is a value type and should know CompareTo. Have you any idea what I am doing wrong, or if I do all wrong? My final aim is to derive classes such these: public class Account : DerivedObject<Account, int> public class ItemGroup : DerivedObject<ItemGroup, string> Big Thanks In Advance!

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  • Multiple generic types in one container

    - by Lirik
    I was looking at the answer of this question regarding multiple generic types in one container and I can't really get it to work: the properties of the Metadata class are not visible, since the abstract class doesn't have them. Here is a slightly modified version of the code in the original question: public abstract class Metadata { } public class Metadata<T> : Metadata { // ... some other meta data public T Function{ get; set; } } List<Metadata> metadataObjects; metadataObjects.Add(new Metadata<Func<double,double>>()); metadataObjects.Add(new Metadata<Func<int,double>>()); metadataObjects.Add(new Metadata<Func<double,int>>()); foreach( Metadata md in metadataObjects) { var tmp = md.Function; // <-- Error: does not contain a definition for Function } The exact error is: error CS1061: 'Metadata' does not contain a definition for 'Function' and no extension method 'Function' accepting a first argument of type 'Metadata' could be found (are you missing a using directive or an assembly reference?) I believe it's because the abstract class does not define the property Function, thus the whole effort is completely useless. Is there a way that we can get the properties?

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  • Memory Leakage using datatables

    - by Vix
    Hi, I have situation in which i'm compelled to retrieve 30,000 records each to 2 datatables.I need to do some manipulations and insert into records into the SQL server in Manipulate(dt1,dt2) function.I have to do this in 15 times as you can see in the for loop.Now I want to know what would be the effective way in terms of memory usage.I've used the first approach.Please suggest me the best approach. (1) for (int i = 0; i < 15; i++) { DataTable dt1 = GetInfo(i); DataTable dt2 = GetData(i); Manipulate(dt1,dt2); } (OR) (2) DataTable dt1 = new DataTable(); DataTable dt2 = new DataTable(); for (int i = 0; i < 15; i++) { dt1=null; dt2=null; dt1 = GetInfo(); dt2 = GetData(); Manipulate(dt1, dt2); } Thanks, Vix.

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  • Creating a C++ DLL and then using it in C#

    - by Major
    Ok I'm trying to make a C++ DLL that I can then call and reference in a c# App. I've already made a simple dll using the numberous guides out there, however when I try to reference it in the C# app I get the error Unable to load DLL 'SDES.dll': The specified module could not be found. The code for the program is as follows (bear with me I'm going to include all the files) //These are the DLL Files. ifndef TestDLL_H define TestDLL_H extern "C" { // Returns a + b __declspec(dllexport) double Add(double a, double b); // Returns a - b __declspec(dllexport) double Subtract(double a, double b); // Returns a * b __declspec(dllexport) double Multiply(double a, double b); // Returns a / b // Throws DivideByZeroException if b is 0 __declspec(dllexport) double Divide(double a, double b); } endif //.cpp include "test.h" include using namespace std; extern double __cdecl Add(double a, double b) { return a + b; } extern double __cdecl Subtract(double a, double b) { return a - b; } extern double __cdecl Multiply(double a, double b) { return a * b; } extern double __cdecl Divide(double a, double b) { if (b == 0) { throw new invalid_argument("b cannot be zero!"); } return a / b; } //C# Program using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Runtime.InteropServices; namespace ConsoleApplication1 { class Program { [DllImport("SDES.dll")] public static extern void SimulateGameDLL(int a, int b); static void Main(string[] args) { SimulateGameDLL(1, 2); //Error here... } } } Anyone have any idea's what I may be missing in my program? Let me know if I missed some code or if you have any questions.

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  • fastest way to check to see if a certain index in a linq statement is null

    - by tehdoommarine
    Basic Details I have a linq statement that grabs some records from a database and puts them in a System.Linq.Enumerable: var someRecords = someRepoAttachedToDatabase.Where(p=>true); Suppose this grabs tons (25k+) of records, and i need to perform operations on all of them. to speed things up, I have to decided to use paging and perform the operations needed in blocks of 100 instead of all of the records at the same time. The Question The line in question is the line where I count the number of records in the subset to see if we are on the last page; if the number of records in subset is less than the size of paging - then that means there are no more records left. What I would like to know is what is the fastest way to do this? Code in Question int pageSize = 100; bool moreData = true; int currentPage = 1; while (moreData) { var subsetOfRecords = someRecords.Skip((currentPage - 1) * pageSize).Take(pageSize); //this is also a System.Linq.Enumerable if (subsetOfRecords.Count() < pageSize){ moreData = false;} //line in question //do stuff to records in subset currentPage++; } Things I Have Considered subsetOfRecords.Count() < pageSize subsetOfRecords.ElementAt(pageSize - 1) == null (causes out of bounds exception - can catch exception and set moreData to false there) Converting subsetOfRecords to an array (converting someRecords to an array will not work due to the way subsetOfRecords is declared - but I am open to changing it) I'm sure there are plenty of other ideas that I have missed.

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  • What's the correct way to pass parameters from VBScript to COM interface implemented in C#?

    - by nopopem
    I'm trying to expose a fairly simple C# class to COM which should be usable from VBScript (among others). Some objects need to be created via COM calls and will be used in furter calls later on. The definition of the exposed classes and interfaces looks like this: namespace Test { [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)] public interface IComInterface { IFoo CreateFoo(); void UseFoo(int x, IFoo f); } [ClassInterface(ClassInterfaceType.None)] public sealed class CComInterface : IComInterface { public CComInterface() {} public IFoo CreateFoo() { return new Foo(); } public void UseFoo(int x, IFoo f) { f.Bar(); } } [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)] public interface IFoo { void Bar(); } [ClassInterface(ClassInterfaceType.None)] public class Foo : IFoo { internal Foo() {} public void Bar() {} } } The simplest thinkable COM client in VBScript does this: Dim ci Set ci = WScript.CreateObject("Test.CComInterface") Dim foo Set foo = ci.CreateFoo foo.Bar ci.UseFoo 0, foo While the call to Bar succeeds, calling UseFoo fails with "Error 5: invalid procedure call or invalid argument" The generated IDL seems ok to me: dispinterface IComInterface { properties: methods: [id(0x60020003)] IFoo* CreateFoo(); [id(0x60020004)] void UseFoo( [in] long x, [in] IFoo* f); }; The vbs call succeeds when I wrap the second parameter in parentheses like this: ci.UseFoo 0, (foo) As far as I understand (I'm no VBScript expert however) this forces the reference to foo to be passed by value, i.e. a copy of the reference is being made. How can I change the interface so that it can be called with the foo reference directly? Since this will be a public interface used by customers I don't like the idea of having to explain why all the objects created need to be passed back in an extra pair of parentheses...

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  • Is there a way to detect Layout or Display changes in WPF?

    Hello! I am trying to check how fast the Frame control can display a FixedPage object when it is assigned to Frame.Content property. I plan to check the tick count before and after the assignment to the Content property. Example: int starttime = Environment.TickCount; frame1.Content = fixedpage; int endtime = Environment.TickCount; The problem is that the assignment to the Content property might be asynchronous and returns immediately therefore i get a zero amount of time. The rendering of the FixedPage however visually has a lag time from assignment of the Content property up to the point where the FixedPage appears on screen. The Frame.ContentChanged() event is no good either because it gets triggered even before the FixedPage appears on screen so it's not accurate. I'm thinking of detecting the change on the window or control's display instead in order to get the time when the FixedPage is actually displayed on screen. Is there a way to do this in WPF? Thanks!

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