How javascript try…catch statement works

Question

I am trying to test in browsermob if certain input field work or not. I am attempting to use a try...catch statement which I have never used before. I know that the form is:

Answer 1

See the “try...catch statement” guide on MDN.

In short, try/catch is used to handle exceptions (which are "thrown" using the throw statement). The syntax for try/catch is:

try {
    // Code
} catch (varName) {              // Optional
    // If exception thrown in try block,
    // execute this block
} finally {                      // Optional
    // Execute this block after
    // try or after catch clause
    // (i.e. this is *always* called)
}

varName is available to the scope of the catch block only. It refers to the exception object which was thrown (which could be any type of object, e.g. a String, but is usually an Error object).