js object length

JavaScript
var size = Object.keys(myObj).length;var person={
    "first_name":"Harry",
    "last_name":"Potter",
    "age":14
};
var personSize = Object.keys(person).length; //gets number of properties (3) Object.size = function(obj) {
    var size = 0, key;
    for (key in obj) {
        if (obj.hasOwnProperty(key)) size++;
    }
    return size;
};

// Get the size of an object
var size = Object.size(myObj);
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