How to remove span tag from WebControl when rendered

Question

When using an ASP.NET CheckBox (and in out case, inherited from a CheckBox) it renders a span around the checkbox input control, this span control

Answer 1

I spent the last 3 hours pulling my hair to find a solution at this problem.

Here is what came out:

using System.Web.UI;
using System.Web.UI.WebControls;

/// 

/// Represents a custom checkbox web control.
/// Prevents itself to be wrapped into a  tag when disabled.
/// 
public class CustomCheckBox : CheckBox
{
    /// 

    /// Renders the control to the specified HTML writer.
    /// 
    /// The HtmlTextWriter object that receives the control content.
    protected override void Render(HtmlTextWriter writer)
    {
        // Use custom writer
        writer = new HtmlTextWriterNoSpan(writer);

        // Call base class
        base.Render(writer);
    }
}

Along with the custom control, you'll need a custom HtmlTextWriter:

using System.IO;
using System.Web.UI;

/// 

/// Represents a custom HtmlTextWriter that displays no span tag.
/// 
public class HtmlTextWriterNoSpan : HtmlTextWriter
{
    /// 

    /// Constructor.
    /// 
    /// Text writer.
    public HtmlTextWriterNoSpan(TextWriter textWriter)
        : base(textWriter)
    { }

    /// 

    /// Determines whether the specified markup element will be rendered to the requesting page.
    /// 
    /// Name.
    /// Tag key.
    /// True if the markup element should be rendered, false otherwise.
    protected override bool OnTagRender(string name, HtmlTextWriterTag key)
    {
        // Do not render  tags
        if (key == HtmlTextWriterTag.Span)
            return false;

        // Otherwise, call the base class (always true)
        return base.OnTagRender(name, key);
    }
}

Just FYI, using:

checkbox.InputAttributes.Add("disabled", "disabled");

has the same effect but:

1. It's not as convenient as checkbox.Enalbed = false;
2. The attribute is removed after a postback when the checkbox is in a ListView.