Question

How can I check if an anonymous object that was created as such:

var myObj = { 
    prop1: 'no',
    prop2: function () { return false; }
}

does indeed have a prop2 defined?

prop2 will always be defined as a function, but for some objects it is not required and will not be defined.

I tried what was suggested here: How to determine if Native JavaScript Object has a Property/Method? but I don’t think it works for anonymous objects .

Answer 1

typeof myObj.prop2 === 'function'; will let you know if the function is defined.

if(typeof myObj.prop2 === 'function') {
    alert("It's a function");
} else if (typeof myObj.prop2 === 'undefined') {
    alert("It's undefined");
} else {
    alert("It's neither undefined nor a function. It's a " + typeof myObj.prop2);
}