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);

    }

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.