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GDI+: A Primer on Building a Color Picker User Control with GDI+ in Visual Basic .NET or C#

Posted By:      Posted Date: August 21, 2010    Points: 0   Category :ASP.Net

Although most developers and APIs use the RGB scheme when working with colors, it's not the only available way to represent or select colors. For instance, the standard Windows color-selection dialog box allows you to work with the HSL color scheme in an indirect way. In this article, the author describes several color selection schemes, and uses GDI+ (via the System.Drawing namespace) to create a component that makes it possible for your own applications to provide a simpler, friendlier color chooser. Along the way, you'll get tips to help you use GDI+ in your own apps.

Ken Getz

MSDN Magazine July 2003

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Building Re-Usable ASP.NET User Control and Page Libraries with VS 2008


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The main project can get a reference to this user control project and can import this user control dll into my main project. 

Thanks in advance,

Dheeraj Mittal


Advanced Basics: Remembering User Information in Visual Basic .NET


Many applications need to store user-specific settings to be persisted between sessions. But how do you go about saving and restoring these settings in your Microsoft® . NET Framework-based application? It's not all that easy to find the correct answer.

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Basic Instincts: Naming and Building Assemblies in Visual Basic .NET


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Delegates in .NET: A Primer on Creating Type-Safe References to Methods in Visual Basic .NET


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Jquery date picker in ASP.NET Web user control does not work


Hello, I have the most frustrating problem and being new to JQuery does make it more difficult. I have an ASP.NET web user control with an ASP.NET box which I want to apply a JQuery date picker to, then of course I have server side code which takes the date and processes it etc. The date picker will not work. I can achieve a working JQuery date picker with an ASP.NET textbox if there is no user control involved, or within the user control I use a html text box instead, but once I add runat="server" to the text box, it does not work. Is there a way I can achieve this? (the web user control will be wrapped in an update panel too which at the moment will work with the html control/web user control without the server side functionality)

<%@ Register TagPrefix="TE" TagName="JobHistory" Src="test.ascx"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">


<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">


    <script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>

    <link h

Building a user control with MVVM

Hi there, I created a custom user control that retrieve rows from database and will create all the buttons on runtime. My current approach is write all codes in the code behind of user control. And also I add a click event handler to each buttons that created on runtime. When any of the button is clicked, inside the click handler function will raise a RoutedEvent. And at the parent control, I add a handler to the custom user control to handle which button is clicked. The problems is : 1) I don't want to write all codes at the code behind. I tried to create a view model class for the user controls, but I failed to bind the event to view model as I wanted to retrieve the object that call this event. ICommand doesn't provide the information for it. 2) Even if I successful created a view model class, when a click event is triggered, the view model will handle it then it fire another event to user control class then the user control class fire another event to the main parent control. Which I think this is stupid >_< 3) I want to know how to user MVVM in this situation. Thanks & Regards, Rambo Ong

AJAX Control Toolkit Color Picker Extendor Control Error


Hi All,

I am using visual studio 2008 with 3.5 framework, I tried color picker extendor control for my application. control is not coming to my page. please guide me on this regards.


Thank you




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I have a Visual Web Part (lets call it "ABCWebPart").

I'm attempting to create a connection to another web part which means I have to create the ConnectionProvider in the WebPart class (ABCWebPart.cs).

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Visual Web part with embedded User Control, fields are null


I have a legacy ASP.Net application that consisted of a series of ascx user controls which I am attempting to convert into visual web parts.  

I have wrapped each ascx in its own visual webpart and deployed to my site. Within my site I am able to add some of these to my pages and they render properly.

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Here is the declaration within CustomerInfoUserControl  and usage …



Help building a user control to track page visits



My intention is to give the user a flexible user control on a master page that does the following:

  1. When navigating, a child page will pass the URL (with querystring) and PageTitle to the user control
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This part works fine through the use of a Repeater with a LinkButton contained in an ItemTemplate. The user sees each of the pages he has been visiting in descending order, the provided benefit is a quick way to re-open records they have recently modified or created.

The part I'm having trouble handling is what happens when the user clicks the LinkButton, which is that the child page adds a new reference to the URL at the beginning of the List<> collection and I cannot seem to control the behavior of removing the LinkButton before it gets re-created. What I've tried doing is:

Repeater1.DataSource = List<>;

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This step-by-step article describes how to call Office macros from a Visual Basic .NET Automation client.

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Download and Share Visual Studio Color Schemes

The good news is that Visual Studio allows you to completely customize the editor background and text colors to whatever you want - allowing you to tweak them to create the experience that is "just right" for your eyes and personality. You can then optionally export/import your color scheme preferences to an XML file via the Tools->Import and Export Settings menu command.

Multiple Instances of User Control


I have a user control that I place on a page severl times.  When I make a selection on a ddl in one one control the SelectedIndexChanged event fires for all the control on the page for that ddl.  So I get duplication of an insert that I do.  Is there a way to make sure these events are isolated so this doesn't happen.


how to get an array of all the asp.net textbox control inside create user wizard control?



How can I get all the textboxes inside a create user wizard control using getElementsByTagName().

Below is my JQuery code:

<script type="text/javascript">
        function addLoadEvent(func) {
            var oldonload = window.onload;
            if (typeof window.onload != 'function') {
                window.onload = func;
            } else {
                window.onload = function() {

        function prepareInputsForHints() {
            var inputs = document.getElementsByTagName("asp:TextBox");
            for (var i = 0; i < inputs.length; i++) {
                inputs[i].onfocus = function() {
                    this.parentNode.getElementsByTagName("span")[0].style.display = "inline";
                inputs[i].onblur = function() {
                    this.parentNode.getElementsByTagName("span")[0].style.display = "none";



<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
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