how to fix loop doesn't iterate through each elment in array code example

Example 1: how to iterate through an array in javascript

const array = ["one", "two", "three"]
array.forEach(function (item, index) {
  console.log(item, index);
});

Example 2: iterate through array javascript

for (var key in validation_messages) {
    // skip loop if the property is from prototype
    if (!validation_messages.hasOwnProperty(key)) continue;

    var obj = validation_messages[key];
    for (var prop in obj) {
        // skip loop if the property is from prototype
        if (!obj.hasOwnProperty(prop)) continue;

        // your code
        alert(prop + " = " + obj[prop]);
    }
}