How to Create Server Controls in ASP.NET

**Liliana** · 14-02-2010

Hi all,

I decided to create my own custom server controls. I try to inherit a label control, but the label control does not support scroll bars. So, I chose to inherit Panel control. The ultimate control with a Panel control all of the properties (color, borders, scroll support, etc.), plus I add some custom attributes. Using the Panel control will make the smallest effort. So i know that how to create server control in ASP.NET. Thanks in advance.

**Praetor** · 14-02-2010

I have built a Custom Server Control for that initialization of the server control is relatively easy. The following is the final code:

Code:

usingSystem;
usingSystem.Collections.Generic;
usingSystem.ComponentModel;
usingSystem.Web.Caching;
usingSystem.Web.UI;
usingSystem.Web.UI.WebControls;

[assembly: TagPrefix ("EndWell123", "EW123")]
namespaceEndWell123
{
[DefaultProperty ("Text")]
[ToolboxData ("<(0): HyperlinkFileList runat ="server">")]
[ToolboxBitmap ("HyperlinkFileList123.ico")]
    
    public classHyperlinkFileList123: Panel
    {
[Bindable (true)]
[Category ("Files List")]
[Description ("The Title of the list of files")]
        public stringFilesTitle123 (get; set;}

[Bindable (true)]
[Category ("Files List")]

**Katty** · 14-02-2010

The server control is basically a div panel built up into a div, and then set the "display" property to "inline-block", to allow multiple controls have been side by side. You can select the following code :

Code:

Style ["display"] = "inline-block";

I do not like the text to the left of the control card, so I add some CSS to fill. I have also controls around the use of some css styles. Check and reply.

**kelfro** · 14-02-2010

I found the control to run every time, it will be re-read the file directory. File input and output price is very expensive. I want to go with the server control's "State". But it uses the View State type, two to send the file list to the client is a very low efficiency. Time as a HTML list, and one in ViewState.So I want to use Session State, Application State and Cache.I have decided to list of files being placed in a cache object. So that the list can be shared between the session. If memory overflow, the cache list will be lost. Check and reply.

**Zecho** · 14-02-2010

I will file directory and file filter connected together, as the cache key. This allows multiple controls at the same time the use and sharing of file list.At first, I added to enable developers to force re-read the documents required functionality. However, the cache object can use the dependency relationship: Any changes will lead to a subordinate directory cache expires. The final code is very simple:

Code:

Page.Cache.Insert (FilesDirectory +FilesFilter, 
m_FilesArray, 
 newCacheDependency (FullPath));

**Reegan** · 14-02-2010

I will you some tips about the Server Controls in ASP.NET. You should not UrlEditor, because it is not allowed to visit the external site's home directory.

Code:

[EditorAttribute (typeof (System.Windows.Forms.Design.FolderNameEditor), typeof (UITypeEditor))]

You do not use FolderNameEditor, because it does not provide a virtual path of choice. In addition, it forces the user to select one I do not want to select the file.