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HtmlTextWriter.GetStyleKey Method

Obtains the HtmlTextWriterStyle enumeration value for the specified style.

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

protected HtmlTextWriterStyle GetStyleKey(
	string styleName
)

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 override void RenderBeginTag(HtmlTextWriterTag tagKey)
{

    // 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)
    {
        if (!IsStyleAttributeDefined(HtmlTextWriterStyle.Color))
        {
            AddStyleAttribute(GetStyleKey("color"), "red");
        }
    }
    // 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)
    {
        if (!IsAttributeDefined(HtmlTextWriterAttribute.Size))
        {
            AddAttribute(GetAttributeKey("size"), "30pt");
        }
    }
    // Call the base class's RenderBeginTag method 
    // to ensure that this custom MarkupTextWriter 
    // includes functionality for all other markup elements. 
    base.RenderBeginTag(tagKey);
}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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