Node.js, MongoDB, and AngularJS Web Development

Throwing Your Own Errors

You can also throw your own errors by using a throw statement. The following code illustrates how to add throw statements to a function to throw an error, even if a script error does not occur. The function sqrRoot() accepts a single argument x. It then tests x to verify that it is a positive number and returns a string with the square root of x. If x is not a positive number, then the appropriate error is thrown, and the catch block returns the error:

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function sqrRoot(x) {    try {        if(x=="")    throw {message:"Can't Square Root Nothing"};        if(isNaN(x)) throw {message:"Can't Square Root Strings"};        if(x<0)      throw {message:"Sorry No Imagination"};        return "sqrt("+x+") ...