DevGuru WMLScript Operator: isvalid



			OPERATOR: isvalid isvalid The isvalid operator is used to test the validity of a variable or the result type of executing an expression. A boolean value is returned to denote the results of the test. A true is returned if the variable or result type is valid. A false is returned if the variable or result type is invalid. Do not confuse this operator with the URL.isValid function which is used to validate the syntax of a URL address string. The classic case of an invalid result type for an expression is dividing by zero. In this example, as expected, the isvalid operator returns a false. Code for IsvalidExample.wml <?xml version="1.0"?> <!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.WAPforum.org/DTD/wml_1.1.xml"> <wml> <card id="card1"> <p> isvalid example </p> <do type="accept"> <go href="IsvalidExample.wmls#findisvalid()" /> </do> </card> <card id="card2"> <p> isvalid = $(valid) </p> </card> </wml> Code for IsvalidExample.wmls extern function findisvalid() { var zerodiv = 1/0; var valid = isvalid(zerodiv); WMLBrowser.setVar("valid", valid); WMLBrowser.go("IsvalidExample.wml#card2"); };