javascript forEach

Iterate over array elements:

var customArray = [3, 5, 7];
customArray.forEach(function(val, index) {
    console.log(val); // 3, 5, 7
});

Iterate over object keys and properties:

var customObject = {'a': 3, 'b': 5, 'c': 7};
Object.keys(customObject).forEach(function(val, index) {
    console.log(val); // a, b, c
    console.log(customObject[val]); // 3, 5, 7
});