Check if object member exists in nested object

Question

Is there a simpler way than using ___ in object to check the existence of each level of an object to check the existence of a single member?

More concisely: How can I check if someObject.member.member.member.value exists?

Answer 1

In general, you can use if(property in object), but this would be still cumbersome for nested members.

You could write a function:

function test(obj, prop) {     var parts = prop.split('.');     for(var i = 0, l = parts.length; i < l; i++) {         var part = parts[i];         if(obj !== null && typeof obj === "object" && part in obj) {             obj = obj[part];         }         else {             return false;         }     }     return true; }  test(someObject, 'member.member.member.value'); 

DEMO

Answer 2

You could also try/catch TypeError?

try {   console.log(someObject.member.member.member.value); } catch(e) {   if (e instanceof TypeError) {     console.log("Couldn't access someObject.member.member.member.value");     console.log(someObject);   } }