Checks to see whether the attribute was passed to the tag. Returns TRUE if the attribute is available; otherwise, returns FALSE.
lpszName
Name of the attribute to check (case insensitive).
Example
The following example checks to see if the user passed an attribute named DESTINATION to the tag and throws an exception if the attribute was not passed:
if ( pRequest->AttributeExists("DESTINATION")==FALSE )
{
pRequest->ThrowException(
"Missing DESTINATION parameter",
"You must pass a DESTINATION parameter in "
"order for this tag to work correctly." ) ;
}