HtmlTextWriter.RenderBeforeTag Méthode

Définition

Écrit tout texte ou espacement survenant avant la balise d'ouverture d'un élément de balisage.Writes any text or spacing that occurs before the opening tag of a markup element.

protected:
 virtual System::String ^ RenderBeforeTag();
protected virtual string RenderBeforeTag ();
abstract member RenderBeforeTag : unit -> string
override this.RenderBeforeTag : unit -> string
Protected Overridable Function RenderBeforeTag () As String

Retours

Texte ou espacement à écrire avant la balise d'ouverture d'un élément de balisage.The text or spacing to write before the markup element opening tag. Si la méthode n'est pas substituée, null.If not overridden, null.

Exemples

L’exemple de code suivant montre comment substituer la RenderBeforeTag méthode pour déterminer si une classe dérivée de la classe HtmlTextWriter est sur le le du rendu <label> d’un élément.The following code example shows how to override the RenderBeforeTag method to determine whether a class that is derived from the HtmlTextWriter class is about to render a <label> element. Dans ce cas, RenderBeforeTag la substitution insère la balise d’ouverture d' <font> un élément immédiatement avant <label> l’élément.If so, the RenderBeforeTag override inserts the opening tag of a <font> element immediately before the <label> element. Si elle ne rend pas un <label> élément, la RenderBeforeTag méthode de base est utilisée.If it is not rendering a <label> element, the RenderBeforeTag base method is used.

// 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

Remarques

La RenderBeforeTag méthode peut être utile si vous souhaitez afficher des balises d’ouverture supplémentaires avant la balise d’ouverture de l’élément prévu.The RenderBeforeTag method can be useful if you want to render additional opening tags before the opening tag of the intended element.

Notes pour les héritiers

L' HtmlTextWriter implémentation de la classe RenderBeforeTag() de la nullméthode retourne.The HtmlTextWriter class implementation of the RenderBeforeTag() method returns null. Substituez RenderBeforeTag() si vous souhaitez écrire du texte ou un espacement avant la balise d’ouverture de l’élément.Override RenderBeforeTag() if you want to write text or spacing ahead of the element opening tag.

S’applique à

Voir aussi