$headerParam
Get the value of the header parameter from the specified string.
Syntax:
$headerParam( string ) $headerParam( string, variable )
Parameters:
string – string
variable – variable name
Returns:
the header parameter’s value.
Version Since:
2.0
Where the function can be used:
- Preliminary rules
- Regular rules
Example:
$headerParam(To)= (.+)
Get all URI parameters from the To header.
$math.le( $headerParam(Contact,"expires"),“3600”) = true
If the “expires” value in Contact header is less than or equal to 3600.