Remove element from JSON Object

To iterate through the keys of an object, use a for .. in loop:

for (var key in json_obj) {
    if (json_obj.hasOwnProperty(key)) {
        // do something with `key'
    }
}

To test all elements for empty children, you can use a recursive approach: iterate through all elements and recursively test their children too.

Removing a property of an object can be done by using the delete keyword:

var someObj = {
    "one": 123,
    "two": 345
};
var key = "one";
delete someObj[key];
console.log(someObj); // prints { "two": 345 }

Documentation:

• https://developer.mozilla.org/en-US/docs/JavaScript/Guide/Working_with_Objects
• https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Statements/for...in
• https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/delete

JSfiddle

function deleteEmpty(obj){
        for(var k in obj)
         if(k == "children"){
             if(obj[k]){
                     deleteEmpty(obj[k]);
             }else{
                   delete obj.children;
              } 
         }
    }

for(var i=0; i< a.children.length; i++){
 deleteEmpty(a.children[i])
}