HtmlTextWriter.IsStyleAttributeDefined Method (HtmlTextWriterStyle)
Determines whether the specified markup style attribute is rendered during the next call to the RenderBeginTag method.
Assembly: System.Web (in System.Web.dll)
Parameters
- key
-
Type:
System.Web.UI.HtmlTextWriterStyle
The HtmlTextWriterStyle associated with the attribute.
Return Value
Type: System.Booleantrue if the attribute will be rendered during the next call to the RenderBeginTag method; otherwise, false.
To get the value that will be rendered with the specified style attribute, use the IsStyleAttributeDefined(HtmlTextWriterStyle, String) overload of the IsStyleAttributeDefined method.
The following code example shows how to check whether a <label> element is being rendered. If so, the IsStyleAttributeDefined method checks whether a Color style attribute has been defined on the element. If the Color attribute has not been defined, the AddStyleAttribute method defines the Color attribute and sets its value to 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"); }
Available since 1.1