HtmlTextWriter.RenderBeforeContent Method

Reference

Definition

Namespace:: System.Web.UI

Assembly:: System.Web.dll

Important

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Writes any text or spacing before the content and after the opening tag of a markup element.

protected:
 virtual System::String ^ RenderBeforeContent();

protected virtual string RenderBeforeContent();

abstract member RenderBeforeContent : unit -> string
override this.RenderBeforeContent : unit -> string

Protected Overridable Function RenderBeforeContent () As String

Returns

String

The text or spacing to write prior to the content of the element. If not overridden, RenderBeforeContent() returns null.

Examples

The following code example shows how to override the RenderBeforeContent method to determine whether a class derived from the HtmlTextWriter class is about to render a <label> element. If so, the RenderBeforeContent override inserts the opening tag of a <font> element immediately after the opening tag of the <label> element. If it is not a <label> element, the RenderBeforeContent base method is used.

// Override the RenderBeforeContent method to write
// a font element that applies red to the text in a Label element.

virtual String^ RenderBeforeContent() override
{
   
   // Check to determine whether the element being rendered
   // is a label element. If so, render the opening tag
   // of the font element; otherwise, call the base method.
   if ( TagKey == HtmlTextWriterTag::Label )
   {
      return "<font color=\"red\">";
   }
   else
   {
      return __super::RenderBeforeContent();
   }
}

// Override the RenderBeforeContent method to write
// a font element that applies red to the text in a Label element.
protected override string RenderBeforeContent()
{
    // Check to determine whether the element being rendered
    // is a label element. If so, render the opening tag
    // of the font element; otherwise, call the base method.
    if (TagKey == HtmlTextWriterTag.Label)
    {
        return "<font color=\"red\">";
    }
    else
    {
        return base.RenderBeforeContent();
    }
}

' Override the RenderBeforeContent method to write
' a font element that applies red to the text in a Label element.
Protected Overrides Function RenderBeforeContent() As String
    ' Check to determine whether the element being rendered
    ' is a label element. If so, render the opening tag
    ' of the font element; otherwise, call the base method.
    If TagKey = HtmlTextWriterTag.Label Then
        Return "<font color=""red"">"
    Else
        Return MyBase.RenderBeforeContent()
    End If
End Function 'RenderBeforeContent

Remarks

The RenderBeforeContent method can be useful if you want to insert child elements into the current markup element before the inner markup.

Notes to Inheritors

The HtmlTextWriter class implementation of the RenderBeforeContent() method returns null. Override RenderBeforeContent() if you want to write text or spacing after the opening tag but ahead of the element content.

Applies to

Product	Versions
.NET Framework	1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

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