HtmlTextWriter.GetStyleKey Method (String)

 

Obtains the HtmlTextWriterStyle enumeration value for the specified style.

Namespace:   System.Web.UI
Assembly:  System.Web (in System.Web.dll)

Protected Function GetStyleKey (
	styleName As String
) As HtmlTextWriterStyle

Parameters

styleName
Type: System.String

The style attribute for which to obtain the HtmlTextWriterStyle.

Return Value

Type: System.Web.UI.HtmlTextWriterStyle

The HtmlTextWriterStyle enumeration value corresponding to styleName.

The GetStyleKey method returns the value -1 typed as a HtmlTextWriterStyle value, if styleName does not correspond to any HtmlTextWriterStyle enumeration value.

The following code example demonstrates how to override the RenderBeginTag method in a class derived from the HtmlTextWriter class. The RenderBeginTag override determines whether a <label> markup will be rendered, and, if so, checks the element for a Color attribute. If a Color attribute has not been defined, the GetStyleKey method is used as the first parameter in a call to the AddStyleAttribute method to add a Color attribute to a <label> markup element and set the Color attribute to red.

' Override the RenderBeginTag method to check whether
' the tagKey parameter is set to a <label> element
' or a <font> element.   
Public Overloads Overrides Sub RenderBeginTag(ByVal tagKey As HtmlTextWriterTag)
    ' If the tagKey parameter is set to a <label> element
    ' but a color attribute is not defined on the element,
    ' the AddStyleAttribute method adds a color attribute
    ' and sets it to red.
    If tagKey = HtmlTextWriterTag.Label Then
        If Not IsStyleAttributeDefined(HtmlTextWriterStyle.Color) Then
            AddStyleAttribute(GetStyleKey("color"), "red")
        End If
    End If

    ' If the tagKey parameter is set to a <font> element
    ' but a size attribute is not defined on the element,
    ' the AddStyleAttribute method adds a size attribute
    ' and sets it to 30 point. 
    If tagKey = HtmlTextWriterTag.Font Then
        If Not IsAttributeDefined(HtmlTextWriterAttribute.Size) Then
            AddAttribute(GetAttributeKey("size"), "30pt")
        End If
    End If

    ' Call the base class's RenderBeginTag method
    ' to ensure that this custom MarkupTextWriter
    ' includes functionality for all other markup elements.
    MyBase.RenderBeginTag(tagKey)
End Sub

.NET Framework
Available since 1.1
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