Creating a generic Web Parts for hosting ASP.NET User Controls

In my previous post, I share a Calendar Web Part solution in C# for SharePoint Portal Server 2003, which demonstrates how to mix web parts and ASP.Net User Controls(.ASCX). Over there, you are forced to hardcode the name and path to a .ASCX file into the web part implementation. The following listing shows a part of codes.


// field to hold reference to user control object
private System.Web.UI.Control _innerUserControl;
// instantiate user control in CreateChildControls
protected override void CreateChildControls()
{
_innerUserControl = this.Page.LoadControl("/wpresources/WebUserControlMonth.ascx");
this.Controls.Add(_innerUserControl);
}
// render user control
protected override void RenderWebPart(HtmlTextWriter output)
{
// output.Write(SPEncode.HtmlEncode(Text));
this.EnsureChildControls();
_innerUserControl.RenderControl(output);
}


There is another solution by Barry Kouda regarding how to create a generic Web Parts for hosting ASP.Net User Control. It's really usefully to design web parts. The following contents show the main method of loading an ASP.NET user control into a Web Part and making it generic.

The approach involves using a shared Web Part property to track the name and path of the .ASCX file. Examine the following code:

// field to hold path to .ASCX file
private string _path;
// Web part property to make path configurable
[ WebPartStorage(Storage.Personal), Category("Miscellaneous"),
FriendlyName("User Control Path"),
Description("Path to .ascx file"),
Browsable(true), DefaultValue("")
]
public string ControlFile {
get { return _path; }
set { _path = value; }
}
// field to hold reference to user control object
Control uc;

// instantiate user control in CreateChildControls
protected override void CreateChildControls() {
this.Controls.Clear();
uc = this.Page.LoadControl(_path);
this.Controls.Add(uc);
}
// render user control
protected override void RenderWebPart(HtmlTextWriter output) {
uc.RenderControl(output);
}[/b]

Now, the file name and path to the .ASCX file are configurable. It’s possible for any SharePoint developer, Web designer or content manager to the UsercontrolHost web part to a web part page and configure the User Control File property through configuration functionality.