Is there a standard function to check for null, undefined, or blank variables in JavaScript?

Question

Is there a universal JavaScript function that checks that a variable has a value and ensures that it\'s not undefined or null? I\'ve got this code,

Answer 1

You are a bit overdoing it. To check if a variable is not given a value, you would only need to check against undefined and null.

function isEmpty(value){
    return (typeof value === "undefined" || value === null);
}

This is assuming 0, "", and objects(even empty object and array) are valid "values".