HtmlTextWriter.IsStyleAttributeDefined Metod

protected:
 bool IsStyleAttributeDefined(System::Web::UI::HtmlTextWriterStyle key);

protected bool IsStyleAttributeDefined(System.Web.UI.HtmlTextWriterStyle key);

member this.IsStyleAttributeDefined : System.Web.UI.HtmlTextWriterStyle -> bool

Protected Function IsStyleAttributeDefined (key As HtmlTextWriterStyle) As Boolean

Parametrar

Returer

true om attributet återges under nästa anrop till RenderBeginTag metoden, annars false.

Exempel

I följande kodexempel visas hur du kontrollerar om ett <label> element återges. I så fall IsStyleAttributeDefined kontrollerar metoden om ett Color formatattribut har definierats för elementet. Color Om attributet inte har definierats AddStyleAttribute definierar Color metoden attributet och anger dess värde till red.

// If the markup element being rendered is a Label,
// render the opening tag of a <Font> element before it.
if ( tagKey == HtmlTextWriterTag::Label )
{
   
   // Check whether a Color style attribute is
   // included on the Label. If not, use the
   // AddStyleAttribute and GetStyleName methods to add one
   // and set its value to red.
   if (  !IsStyleAttributeDefined( HtmlTextWriterStyle::Color ) )
   {
      AddStyleAttribute( GetStyleName( HtmlTextWriterStyle::Color ), "red" );
   }

// If the markup element being rendered is a Label,
// render the opening tag of a Font element before it.
if (tagKey == HtmlTextWriterTag.Label)
{
    // Check whether a Color style attribute is 
    // included on the Label. If not, use the
    // AddStyleAttribute and GetStyleName methods to add one
    // and set its value to red.
    if (!IsStyleAttributeDefined(HtmlTextWriterStyle.Color))
    {
        AddStyleAttribute(GetStyleName(HtmlTextWriterStyle.Color), "red");
    }

' If the markup element being rendered is a Label,
' render the opening tag of a Font element before it.
If tagKey = HtmlTextWriterTag.Label Then
    ' Check whether a Color style attribute is 
    ' included on the Label. If not, use the
    ' AddStyleAttribute and GetStyleName methods to add one
    ' and set its value to red.
    If Not IsStyleAttributeDefined(HtmlTextWriterStyle.Color) Then
        AddStyleAttribute(GetStyleName(HtmlTextWriterStyle.Color), "red")
    End If

Kommentarer

Om du vill hämta värdet som ska återges med det angivna formatattributet använder du IsStyleAttributeDefined(HtmlTextWriterStyle, String) metodens IsStyleAttributeDefined överlagring.

Se även

• TextWriter
• HtmlTextWriterStyle
• RenderBeginTag

protected:
 bool IsStyleAttributeDefined(System::Web::UI::HtmlTextWriterStyle key, [Runtime::InteropServices::Out] System::String ^ % value);

protected bool IsStyleAttributeDefined(System.Web.UI.HtmlTextWriterStyle key, out string value);

member this.IsStyleAttributeDefined : System.Web.UI.HtmlTextWriterStyle * string -> bool

Protected Function IsStyleAttributeDefined (key As HtmlTextWriterStyle, ByRef value As String) As Boolean

Parametrar

Returer

true om attributet och dess värde återges under nästa anrop till RenderBeginTag metoden, falseannars .

Kommentarer

IsStyleAttributeDefined Om metoden returnerar truereturneras värdet som ska tilldelas till HtmlTextWriterStyle attributet i parameternvalue.

Se även

• TextWriter
• HtmlTextWriterStyle
• RenderBeginTag