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  • Passing objects by reference or not in C#

    - by Piku
    Suppose I have a class like this: public class ThingManager { List<SomeClass> ItemList; public void AddToList (SomeClass Item) { ItemList.Add(Item); } public void ProcessListItems() { // go through list one item at a time, get item from list, // modify item according to class' purpose } } Assume "SomeClass" is a fairly large class containing methods and members that are quite complex (List<s and arrays, for example) and that there may be a large quantity of them, so not copying vast amounts of data around the program is important. Should the "AddToList" method have "ref" in it or not? And why? It's like trying to learn pointers in C all over again ;-) (which is probably why I am getting confused, I'm trying to relate these to pointers. In C it'd be "SomeClass *Item" and a list of "SomeClass *" variables)

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  • WPF ResourceDictionary and DynamicResource

    - by lanicor
    i am new to WPF so maybe this will be "noob" question but i can't find answer to it (and it seems so easy)... well i am programing WPF app and i want to use smth similar to css for webpages, so i found ResourceDictionary and tried to use it... I have main window in which i create Frame and on click some UserControl is loaded to that same Frame.I include my ResourceDictionary (root/style/Styles.xaml) to my main window like this: <Window.Resources> <ResourceDictionary x:Key="styles" Source="style/Styles.xaml" /> </Window.Resources> in which i have: <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <Style x:Key="ProductsRequired" TargetType="{x:Type Label}"> <Setter Property="Height" Value="28" /> ... I don't use it on my main window but want to use it on my UserControls, which are loaded to that main window and i try to use it like this: <Label Name="product1" Style="{DynamicResource ProductsRequired}" /> Warning i am getting all the time is: The resource "ProductsRequired" could not be resolved. I even tried including Styles to my UserControl <UserControl.Resources> <ResourceDictionary x:Key="styles" Source="../style/Styles.xaml" /> </UserControl.Resources> and nothing happens... Well my question is long but i wanted to be clear... :) P.S. all that logic works in C# code btw private ResourceDictionary myStyles = new ResourceDictionary(); Style ProductsRequired = myStyles["ProductsRequired"] as Style; product1.Style = ProductsRequired;

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  • LWJGL Circle program create's an oval-like shape

    - by N1ghtk1n9
    I'm trying to draw a circle in LWJGL, but when I draw I try to draw it, it makes a shape that's more like an oval rather than a circle. Also, when I change my circleVertexCount 350+, the shape like flips out. I'm really not sure how the code works that creates the vertices(I have taken Geometry and I know the basic trig ratios). I haven't really found that good of tutorials on creating circles. Here's my code: public class Circles { // Setup variables private int WIDTH = 800; private int HEIGHT = 600; private String title = "Circle"; private float fXOffset; private int vbo = 0; private int vao = 0; int circleVertexCount = 300; float[] vertexData = new float[(circleVertexCount + 1) * 4]; public Circles() { setupOpenGL(); setupQuad(); while (!Display.isCloseRequested()) { loop(); adjustVertexData(); Display.update(); Display.sync(60); } Display.destroy(); } public void setupOpenGL() { try { Display.setDisplayMode(new DisplayMode(WIDTH, HEIGHT)); Display.setTitle(title); Display.create(); } catch (LWJGLException e) { e.printStackTrace(); System.exit(-1); } glClearColor(0.0f, 0.0f, 0.0f, 0.0f); } public void setupQuad() { float r = 0.1f; float x; float y; float offSetX = 0f; float offSetY = 0f; double theta = 2.0 * Math.PI; vertexData[0] = (float) Math.sin(theta / circleVertexCount) * r + offSetX; vertexData[1] = (float) Math.cos(theta / circleVertexCount) * r + offSetY; for (int i = 2; i < 400; i += 2) { double angle = theta * i / circleVertexCount; x = (float) Math.cos(angle) * r; vertexData[i] = x + offSetX; } for (int i = 3; i < 404; i += 2) { double angle = Math.PI * 2 * i / circleVertexCount; y = (float) Math.sin(angle) * r; vertexData[i] = y + offSetY; } FloatBuffer vertexBuffer = BufferUtils.createFloatBuffer(vertexData.length); vertexBuffer.put(vertexData); vertexBuffer.flip(); vao = glGenVertexArrays(); glBindVertexArray(vao); vbo = glGenBuffers(); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferData(GL_ARRAY_BUFFER,vertexBuffer, GL_STATIC_DRAW); glVertexAttribPointer(0, 2, GL_FLOAT, false, 0, 0); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArray(0); } public void loop() { glClear(GL_COLOR_BUFFER_BIT); glBindVertexArray(vao); glEnableVertexAttribArray(0); glDrawArrays(GL_TRIANGLE_FAN, 0, vertexData.length / 2); glDisableVertexAttribArray(0); glBindVertexArray(0); } public static void main(String[] args) { new Circles(); } private void adjustVertexData() { float newData[] = new float[vertexData.length]; System.arraycopy(vertexData, 0, newData, 0, vertexData.length); if(Keyboard.isKeyDown(Keyboard.KEY_W)) { fXOffset += 0.05f; } else if(Keyboard.isKeyDown(Keyboard.KEY_S)) { fXOffset -= 0.05f; } for(int i = 0; i < vertexData.length; i += 2) { newData[i] += fXOffset; } FloatBuffer newDataBuffer = BufferUtils.createFloatBuffer(newData.length); newDataBuffer.put(newData); newDataBuffer.flip(); glBindBuffer(GL_ARRAY_BUFFER, vbo); glBufferSubData(GL_ARRAY_BUFFER, 0, newDataBuffer); glBindBuffer(GL_ARRAY_BUFFER, 0); } } 300 Vertex Count(This is my main problem) 400 Vertex Count - I removed this image, it's bugged out, should be a tiny sliver cut out from the right, like a secant 500 Vertex Count Each 100, it removes more and more of the circle, and so on.

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  • How to pass event to method?

    - by tomaszs
    I would like to create a method that takes as a argument an event an adds eventHandler to it to handle it properly. Like this: I have 2 events: public event EventHandler Click; public event EventHandler Click2; Now i would like to pass particular event to my method like this (pseudocode): public AttachToHandleEvent(EventHandler MyEvent) { MyEvent += Item_Click; } private void Item_Click(object sender, EventArgs e) { MessageBox.Show("lalala"); } ToolStripMenuItem tool = new ToolStripMenuItem(); AttachToHandleEvent(tool.Click); Is it possible or do I not understand it good? Edit: I've noticed with help of you that this code worked fine, and returned to my project and noticed that when I pass event declared in my class it works, but when I pass event from other class id still does not work. Updated above example to reflect this issue. What I get is this error: The event 'System.Windows.Forms.ToolStripItem.Click' can only appear on the left hand side of += or -=

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  • Java FileFilter

    - by Mr CooL
    public class DocFilter extends FileFilter { public boolean accept(File f) { if (f.isDirectory()) { return true; } String extension = Utils.getExtension(f); if (extension != null) { if (extension.equals(Utils.doc) || extension.equals(Utils.docx) ) { return true; } else { return false; } } return false; } //The description of this filter public String getDescription() { return "Just Document Files"; } } Netbeans compiler warned with the error, "No interface expected here" for above code Anyone has idea what was the problem?? I tried changing the 'extends' to 'implements', however, it didn't seem to work that way. and when I changed to implements, the following code cannot work, chooser.addChoosableFileFilter(new DocFilter()); and with this error, "method addChoosableFileFilter in class javax.swing.JFileChooser cannot be applied to given types required: javax.swing.filechooser.FileFilter" Can anyone help on this? Thanks..

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  • Does this variable need to be declared volatile?

    - by titaniumdecoy
    Does the out variable in the MyThread class need to be declared volatile in this code or will the "volatility" of the stdout variable in the ThreadTest class carry over? import java.io.PrintStream; class MyThread implements Runnable { int id; PrintStream out; // should this be declared volatile? MyThread(int id, PrintStream out) { this.id = id; this.out = out; } public void run() { try { Thread.currentThread().sleep((int)(1000 * Math.random())); out.println("Thread " + id); } catch (InterruptedException e) { e.printStackTrace(); } } } public class ThreadTest { static volatile PrintStream stdout = System.out; public static void main(String[] args) { for (int i = 0; i < 10; i++) { new Thread(new MyThread(i, stdout)).start(); } } }

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  • Can't get Javac to work on Mac OS X

    - by elguapo-85
    I am trying to compile with javac on Snow Leopard through the command line. I have Xcode installed. I am just using a simple Hello World file, it works in Eclipse but I can't get it to work using javac. javac -version returns javac 1.6.0_17 HelloWorld.java public class HelloWorld { public static void main(String[] args) { String message = "Welcome to Java!"; System.out.println(message); } } I type: javac HelloWorld.java and get the following error. HelloWorld.java:1: class, interface, or enum expected public class HelloWorld ^ 1 error and... javac -cp . HelloWorld.java returns the same. echo $CLASSPATH just returns blank. Thanks for the help.

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  • Interesting LinqToSql behaviour

    - by Ben Robinson
    We have a database table that stores the location of some wave files plus related meta data. There is a foreign key (employeeid) on the table that links to an employee table. However not all wav files relate to an employee, for these records employeeid is null. We are using LinqToSQl to access the database, the query to pull out all non employee related wav file records is as follows: var results = from Wavs in db.WaveFiles where Wavs.employeeid == null; Except this returns no records, despite the fact that there are records where employeeid is null. On profiling sql server i discovered the reason no records are returned is because LinqToSQl is turning it into SQL that looks very much like: SELECT Field1, Field2 //etc FROM WaveFiles WHERE 1=0 Obviously this returns no rows. However if I go into the DBML designer and remove the association and save. All of a sudden the exact same LINQ query turns into SELECT Field1, Field2 //etc FROM WaveFiles WHERE EmployeeID IS NULL I.e. if there is an association then LinqToSql assumes that all records have a value for the foreign key (even though it is nullable and the property appears as a nullable int on the WaveFile entity) and as such deliverately constructs a where clause that will return no records. Does anyone know if there is a way to keep the association in LinqToSQL but stop this behaviour. A workaround i can think of quickly is to have a calculated field called IsSystemFile and set it to 1 if employeeid is null and 0 otherwise. However this seems like a bit of a hack to work around strange behaviour of LinqToSQl and i would rather do something in the DBML file or define something on the foreign key constraint that will prevent this behaviour.

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  • Does importing of packages change visibility of classes?

    - by Roman
    I jsut learned that A class may be declared with the modifier public, in which case that class is visible to all classes everywhere. If a class has no modifier (the default, also known as package-private), it is visible only within its own package. This is a clear statement. But this information interfere with my understanding of importing of packages (which easily can be wrong). I thought that importing a package I make classes from the imported package visible to the importing class. So, how does it work? Are public classes visible to all classes everywhere under condition that the package containing the public class is imported? Or there is not such a condition? What about the package-private classes? They are invisible no mater if the containing package was imported or not? ADDED: It seems to me that I got 2 answers which are marked as good (up-voted) and which contradict eachother.

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  • Using switch and enumerations as substitute for named methods

    - by MatthewMartin
    This pattern pops up a lot. It looks like a very verbose way to move what would otherwise be separate named methods into a single method and then distinguished by a parameter. Is there any good reason to have this pattern over just having two methods Method1() and Method2() ? The real kicker is that this pattern tends to be invoked only with constants at runtime-- i.e. the arguments are all known before compiling is done. public enum Commands { Method1, Method2 } public void ClientCode() { //Always invoked with constants! Never user input. RunCommands(Commands.Method1); RunCommands(Commands.Method2); } public void RunCommands(Commands currentCommand) { switch (currentCommand) { case Commands.Method1: // Stuff happens break; case Commands.Method2: // Other stuff happens break; default: throw new ArgumentOutOfRangeException("currentCommand"); } }

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  • How do I get property injection working in Ninject for a ValidationAttribute in MVC?

    - by jaltiere
    I have a validation attribute set up where I need to hit the database to accomplish the validation. I tried setting up property injection the same way I do elsewhere in the project but it's not working. What step am I missing? public class ApplicationIDValidAttribute : ValidationAttribute { [Inject] protected IRepository<MyType> MyRepo; public override bool IsValid(object value) { if (value == null) return true; int id; if (!Int32.TryParse(value.ToString(), out id)) return false; // MyRepo is null here and is never injected var obj= MyRepo.LoadById(id); return (obj!= null); } One other thing to point out, I have the Ninject kernel set up to inject non-public properties, so I don't think that is the problem. I'm using Ninject 2, MVC 2, and the MVC 2 version of Ninject.Web.MVC. Thanks!

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  • Is this crufty?

    - by bobobobo
    I'm writing code like: class Game { int getMouseX() { return inputManager.getMouseX() ; } } ; I remember seeing code like this and hating it. One function passes off to another? What is this "pattern" (or, possibly, anti-pattern) called? I don't like it! On the other hand, it saves exposing the InputManager to the user of the class... would that be a better choice? Or should Game simply not contain InputManager? Edit What about using multiple inheritance instead? class Game : public InputManager, public Window { // by virtue of inheriting InputManager and Window, // Game now has "acquired" the capabilities of // InputManager's public functions, without requiring delegate. } ; Have I not found a reasonably good use for multiple inheritance??

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  • How To Use ObjectDataSource With Complex Objects and FormView Control

    - by obautista
    I have a complex object. For example a SCHOOL object that contains a collection of PERSON object. How can I use the ObjectDataSource control with a FormView and flatten the complex object? An example display would be to display the school name and comma separate the students on the page. Is this possible? I.E. public string Id { get { return m_id; } set { m_id = value; } } public string SchoolName { get { return m_schoolName; } set { m_schoolName = value; } } public List(Person Students { get { return m_students; } set { m_cast = students; } }

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  • Convert this VB code to C#?

    - by Róisín Kerr Lautman
    I was wondering if anyone would be able to help me convert the below code to c#? From what I have read it seems to be similar however I am not sure if my 'case' statements are still able to be used? Public Class Form1 Dim dteStart As Date Dim dteFinish As Date Dim span As TimeSpan Public Sub KeyDown(ByVal Sender As System.Object, ByVal e As _ System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyDown Select Case e.KeyCode Case Keys.Q Label1.BackColor = Color.Green dteStart = Now() Case Keys.W Label2.BackColor = Color.Green Case Keys.E Label3.BackColor = Color.Green Case Keys.R Label4.BackColor = Color.Green dteFinish = Now() span = dteFinish.Subtract(dteStart) Label5.Text = span.ToString End Select End Sub Public Sub KeyUp(ByVal Sender As System.Object, ByVal e As _ System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyUp Select Case e.KeyCode Case Keys.Q Label1.BackColor = Color.Red Case Keys.W Label2.BackColor = Color.Red Case Keys.E Label3.BackColor = Color.Red Case Keys.R Label4.BackColor = Color.Red End Select End Sub End Class

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  • NUnit Assert a list of objects in no order

    - by Shawn Mclean
    How do I Assert a collection of items in no particular order? I just want to make sure all the items are in the list. I'm heard of CollectionAssert but I do not see any method that would do what I want. My object looks like this: public class Vector2{ public float X {get; set;} public float Y {get; set;} } Assert - I want something like this: CollectionAssert.ContainsAll(mesh.GetPolygonVertices(0), aListOfVertices); mesh.GetPolygonVertices(int) returns a List<Vector2> and aListOfVertices contains all of what is returned, but not guaranteed that order.

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  • Question of using static_cast on "this" pointer in a derived object to base class

    - by Johnyy
    Hi, this is an example taken from Effective C++ 3ed, it says that if the static_cast is used this way, the base part of the object is copied, and the call is invoked from that part. I wanted to understand what is happening under the hood, will anyone help? class Window { // base class public: virtual void onResize() { } // base onResize impl }; class SpecialWindow: public Window { // derived class public: virtual void onResize() { // derived onResize impl; static_cast<Window>(*this).onResize(); // cast *this to Window, // then call its onResize; // this doesn't work! // do SpecialWindow- } // specific stuff };

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  • Threading multiple WebBrowser in VB .net

    - by Code_Seeker
    I'm building a multiple webbrowser inside tabs( 1 predefine webbrowser control per tab) and I want them all to load at the same time or other words must run in thread. Unfortunately I feel a valid fact came from the error message that this is something not possible. Pls help me to check my simple program code below and its error in case i tried releasing 2 webbrowser controls but when I leave it to single web browser control it works fine. Any workaround? Imports System.Threading Public Class Form1 Dim mythread1 As Thread Dim mythread2 As Thread Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load mythread1 = New Thread(AddressOf mysub1) mythread2 = New Thread(AddressOf mysub2) mythread1.IsBackground = True mythread2.IsBackground = True mythread1.Start() mythread2.Start() End Sub Public Sub mysub1() Dim HTML As String WebBrowser1.Navigate("about:blank") mythread1.Abort() End Sub Public Sub mysub2() WebBrowser2.Navigate("about:blank") mythread2.Abort() End Sub

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  • In a combobox, how do I determine the highlighted item (not selected item)?

    - by Harold Bamford
    First, fair warning: I am a complete newbie with C# and WPF. I have a combobox (editable, searchable) and I would like to be able to intercept the Delete key and remove the currently highlighted item from the list. The behavior I'm looking for is like that of MS Outlook when entering in email addresses. When you give a few characters, a dropdown list of potential matches is displayed. If you move to one of these (with the arrow keys) and hit Delete, that entry is permanently removed. I want to do that with an entry in the combobox. Here is the XAML (simplified): <ComboBox x:Name="Directory" KeyUp="Directory_KeyUp" IsTextSearchEnabled="True" IsEditable="True" Text="{Binding Path=CurrentDirectory, Mode=TwoWay}" ItemsSource="{Binding Source={x:Static self:Properties.Settings.Default}, Path=DirectoryList, Mode=TwoWay}" / The handler is: private void Directory_KeyUp(object sender, KeyEventArgs e) { ComboBox box = sender as ComboBox; if (box.IsDropDownOpen && (e.Key == Key.Delete)) { TrimCombobox("DirectoryList", box.HighlightedItem); // won't compile! } } When using the debugger, I can see box.HighlightedItem has the value I want but when I try and put in that code, it fails to compile with: System.Windows.Controls.ComboBox' does not contain a definition for 'HighlightedItem'... So: how do I access that value? Keep in mind that the item has not been selected. It is merely highlighted as the mouse hovers over it. Thanks for your help.

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  • csv to hash data structure conversion using perl

    - by Kavya S
    1. Convert a .csv file to perlhash data structure Format of a .csv file: sw,s1,s2,s3,s4 ver,v1,v2,v3,v4 msword,v2,v3,v1,v1 paint,v4,v2,v3,v3 outlook,v1,v1,v3,v2 my perl script: #!/usr/local/bin/perl use strict; use warnings; use Data::Dumper; my %hash; open my $fh, '<', 'some_file.csv' or die "Cannot open: $!"; while (my $line = <$fh>) { $line =~ s/,,/-/; chomp ($line); my @array = split /,/, $line; my $key = shift @array; $hash{$key} = $line; $hash{$key} = \@array; } print Dumper(\%hash); close $fh; perl hash i.e output should look like: $sw_ver_db = { s1 => { msword => {ver => v2}, paint => {ver => v4}, outlook => {ver => v1}, }, s2 => { msword => {ver => v3}, paint => {ver => v2}, outlook => {ver => v1}, }, s3 => { msword => {ver =>v1}, paint => {ver =>v3}, outlook => {ver =>v3}, }, s4 => { msword => {ver =>v1}, paint => {ver =>v3}, outlook => {ver =>v2}, }, };

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  • Strange results from OdbcDataReader reading Sqlite DB

    - by stout
    This method returns some strange results, and was wondering if someone could explain why this is happening, and possibly a solution to get my desired results. Results: FileName = what I'd expect FileSize = what I'd expect Buffer = all bytes = 0 BytesRead = 0 BlobString = string of binary data FieldType = BLOB (what I'd expect) ColumnType = System.String Furthermore, if the file is greater than a few KB, the reader throws an exception stating the StringBuilder capacity argument must be greater than zero (presummably because the size is greater than Int32.MaxValue). I guess my question is how does one properly read large BLOBs from an OdbcDataReader? public static String SaveBinaryFile(String Key) { try { Connect(); OdbcCommand Command = new OdbcCommand("SELECT [_filename_],[_filesize_],[_content_] FROM [_sys_content] WHERE [_key_] = '" + Key + "';", Connection); OdbcDataReader Reader = Command.ExecuteReader(CommandBehavior.SequentialAccess); if (Reader.HasRows == false) return null; String FileName = Reader.GetString(0); int FileSize = int.Parse(Reader.GetString(1)); byte[] Buffer = new byte[FileSize]; long BytesRead = Reader.GetBytes(2, 0, Buffer, 0, FileSize); String BlobString = (String)Reader["_content_"]; String FieldType = Reader.GetDataTypeName(2); Type ColumnType = Reader.GetFieldType(2); return null; } catch (Exception ex) { Tools.ErrorHandler.Catch(ex); return null; } }

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  • Swing Timer in Conjunction with Possible Long-running Background Task

    - by javacavaj
    I need to perform a task repeatedly that affects both GUI-related and non GUI-related objects. One caveat is that no action should performed if the previous task had not completed when the next timer event is fired. My initial thoughts are to use a SwingTimer in conjunction with a javax.swing.SwingWorker object. The general setup would look like this. class { timer = new Timer(speed, this); timer.start(); public void actionPerformed(ActionEvent e) { SwingWorker worker = new SwingWorker() { @Override public ImageIcon[] doInBackground() { // potential long running task } @Override public void done() { // update GUI on event dispatch thread when complete } } } Some potential issues I see with this approach are: 1) Multiple SwingWorkers will be active if a worker has not completed before the next ActionEvent is fired by the timer. 2) A SwingWorker is only designed to be executed once, so holding a reference to the worker and reusing (is not?) a viable option. Is there a better way to achieve this?

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  • Incorrect emacs indentation in a C++ class with DLL export specification

    - by Michael Daum
    I often write classes with a DLL export/import specification, but this seems to confuse emacs' syntax parser. I end up with something like: class myDllSpec Foo { public: Foo( void ); }; Notice that the "public:" access spec is indented incorrectly, as well as everything that follows it. When I ask emacs to describe the syntax at the beginning of the line containing public, I get a return of: ((label 352)) If I remove the myDllSpec, the indentation is correct, and emacs tells me that the syntax there is: ((inclass 352) (access-label 352)) Which seems correct and reasonable. So I conclude that the syntax parser is not able to handle the DLL export spec, and that this is what's causing my indentation trouble. Unfortunately, I don't know how to teach the parser about my labels. Seems that this is pretty common practice, so I'm hoping there's a way around it.

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  • What is the fastest way to filter a list of strings when making an Intellisense/Autocomplete list?

    - by user559548
    Hello everyone, I'm writing an Intellisense/Autocomplete like the one you find in Visual Studio. It's all fine up until when the list contains probably 2000+ items. I'm using a simple LINQ statement for doing the filtering: var filterCollection = from s in listCollection where s.FilterValue.IndexOf(currentWord, StringComparison.OrdinalIgnoreCase) >= 0 orderby s.FilterValue select s; I then assign this collection to a WPF Listbox's ItemSource, and that's the end of it, works fine. Noting that, the Listbox is also virtualised as well, so there will only be at most 7-8 visual elements in memory and in the visual tree. However the caveat right now is that, when the user types extremely fast in the richtextbox, and on every key up I execute the filtering + binding, there's this semi-race condition, or out of sync filtering, like the first key stroke's filtering could still be doing it's filtering or binding work, while the fourth key stroke is also doing the same. I know I could put in a delay before applying the filter, but I'm trying to achieve a seamless filtering much like the one in Visual Studio. I'm not sure where my problem exactly lies, so I'm also attributing it to IndexOf's string operation, or perhaps my list of string's could be optimised in some kind of index, that could speed up searching. Any suggestions of code samples are much welcomed. Thanks.

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  • select from multiple tables but ordering by a datetime field

    - by Chris Mccabe
    I have 3 tables that are unrelated (related that each contains data for a different social network). Each has a datetime field dated- I'm already grouping by hour as you can see below (this one below for linked_in) SELECT count(*), date_format(dated, '%Y:%m:%d %H') as hour FROM upd8r_linked_in_accts WHERE CAST(dated AS DATE) = '".$start_date."' GROUP BY hour I would like to know how to do a total across all 3 networks- the tables for the three are CREATE TABLE IF NOT EXISTS `upd8r_facebook_accts` ( `id` int(11) NOT NULL AUTO_INCREMENT, `owner_id` varchar(50) NOT NULL, `user_id` int(11) NOT NULL, `fb_id` bigint(30) NOT NULL, `dated` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=80 ; CREATE TABLE IF NOT EXISTS `upd8r_linked_in_accts` ( `id` int(11) NOT NULL AUTO_INCREMENT, `owner_id` varchar(50) NOT NULL, `user_id` int(11) NOT NULL, `linked_in` varchar(200) NOT NULL, `oauth_secret` varchar(100) NOT NULL, `first_count` int(11) NOT NULL, `second_count` int(11) NOT NULL, `dated` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=200 ; CREATE TABLE IF NOT EXISTS `upd8r_twitter_accts` ( `id` int(11) NOT NULL AUTO_INCREMENT, `owner_id` varchar(50) NOT NULL, `user_id` int(11) NOT NULL, `twitter` varchar(200) NOT NULL, `twitter_secret` varchar(100) NOT NULL, `dated` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=9 ; something like this ? (SELECT count(*), date_format(dated, '%Y:%m:%d %H') as hour FROM upd8r_linked_in_accts WHERE CAST(dated AS DATE) = '".$start_date."') UNION ALL (SELECT count(*), date_format(dated, '%Y:%m:%d %H') as hour FROM upd8r_facebook_accts WHERE CAST(dated AS DATE) = '".$start_date."') UNION ALL (SELECT count(*), date_format(dated, '%Y:%m:%d %H') as hour FROM upd8r_twitter_accts WHERE CAST(dated AS DATE) = '".$start_date."') UNION ALL GROUP BY hour

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  • which toString() method can be used performance wise??

    - by Mrityunjay
    hi, I am working on one project for performance enhancement. I had one doubt, while we are during a process, we tend to trace the current state of the DTO and entity used. So, for this we have included toString() method in all POJOs for the same. I have now implemented toString() in three different ways which are following :- public String toString() { return "POJO :" + this.class.getName() + " RollNo :" + this.rollNo + " Name :" + this.name; } public String toString() { StringBuffer buff = new StringBuffer("POJO :").append(this.class.getName()).append(" RollNo :").append(this.rollNo).append(" Name :").append(this.name); return buff.toString(); } public String toString() { StringBuilder builder = new StringBuilder("POJO :").append(this.class.getName()).append(" RollNo :").append(this.rollNo).append(" Name :").append(this.name); return builder .toString(); } can anyone please help me to find out which one is best and should be used for enhancing performance.

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