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HtmlTextWriter.TagName Property

  • Reference

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Gets or sets the tag name of the markup element being rendered.

protected:
 property System::String ^ TagName { System::String ^ get(); void set(System::String ^ value); };
protected string TagName { get; set; }
member this.TagName : string with get, set
Protected Property TagName As String

Property Value

String

The tag name of the markup element being rendered.

Examples

The following code example demonstrates an overridden version of the RenderBeforeTag method in a class that derives from the HtmlTextWriter class. The code example checks whether the element to render is a <label> element by calling the String.Compare method, and then passing the TagName property value and a string, "label", as the parameter arguments. If a <label> element is about to be rendered, the opening tag of a <font> element, with a color attribute set to red, is rendered before the <label> element's opening tag. If the element to render is not a <label> element, the base class's version of the RenderBeforeTag method is called.

// Override the RenderBeforeTag method to add the
// opening tag of a Font element before the
// opening tag of any Label elements rendered by this
// custom markup writer.
virtual String^ RenderBeforeTag() override
{
   // Compare the TagName property value to the
   // String* label to determine whether the element to
   // be rendered is a Label. If it is a Label,
   // the opening tag of the Font element, with a Color
   // style attribute set to red, is added before
   // the Label.
   if ( String::Compare( TagName, "label" ) == 0 )
   {
      return "<font color=\"red\">";
   }
   // If a Label is not being rendered, use
   // the base RenderBeforeTag method.
   else
   {
      return __super::RenderBeforeTag();
   }
}

// Override the RenderBeforeTag method to add the 
// opening tag of a Font element before the 
// opening tag of any Label elements rendered by this 
// custom markup writer. 
protected override string RenderBeforeTag()
{
    // Compare the TagName property value to the
    // string label to determine whether the element to 
    // be rendered is a Label. If it is a Label,
    // the opening tag of the Font element, with a Color
    // style attribute set to red, is added before
    // the Label.
    if (String.Compare(TagName, "label") == 0)
    {
        return "<font color=\"red\">";
    }
    // If a Label is not being rendered, use 
        // the base RenderBeforeTag method.
    else
    {
        return base.RenderBeforeTag();
    }
}

' Override the RenderBeforeTag method to add the 
' opening tag of a Font element before the 
' opening tag of any Label elements rendered by this 
' custom markup writer. 
Protected Overrides Function RenderBeforeTag() As String
    ' Compare the TagName property value to the
    ' string label to determine whether the element to 
    ' be rendered is a Label. If it is a Label,
    ' the opening tag of the Font element, with a Color
    ' style attribute set to red, is added before
    ' the Label.
    If String.Compare(TagName, "label") = 0 Then
        Return "<font color=""red"">"
        ' If a Label is not being rendered, use 
        ' the base RenderBeforeTag method.
    Else
        Return MyBase.RenderBeforeTag()
    End If
End Function 'RenderBeforeTag

Remarks

The TagName property is of use only to classes that inherit from the HtmlTextWriter class. You should read or set the TagName property only in RenderBeginTag method calls; this is the only time it is set to a consistent value.

Applies to

See also