JavaScript Handling of exceptions

JavaScript provides a set of exception handling mechanisms. When an accident is detected, your program should throw an exception:

var add=function(b) {    if(typeoftypeof B!== ' number ' {        throw  {            name:' TypeError ',            message:' Add needs numbers '         }    }    return a + b;}

The throw statement then interrupts the execution of the function. It throws a exception object that contains the Name property that recognizes the exception type and a descriptive message property. You can also add additional properties.

The exception object is passed to the catch clause of a try statement:

var try_it=function() {    try{        Add ("seven");    } Catch (e) {        Document.writeln (e.name+ ': ' +e.message);    }}
Try_it ();

A try statement will only have a catch code block that will catch all exceptions.

JavaScript Handling of exceptions