angularjsHow can I use AngularJS to watch an array for changes?

AngularJS provides a $watch function for watching an array for changes. This function takes two arguments: the array to watch and a callback function that will be called when the array changes.

var arr = [1, 2, 3];
$scope.$watch(arr, function (newArr, oldArr) {
  console.log('Array changed from', oldArr, 'to', newArr);
});

arr.push(4);
// Output: Array changed from [1, 2, 3] to [1, 2, 3, 4]

The $watch function takes two arguments:

1. The array to watch (arr in the example above).
2. A callback function that will be called when the array changes (function (newArr, oldArr) in the example above). The callback function takes two arguments: the new array (newArr) and the old array (oldArr).

In the example code above, the $watch function is used to watch the arr array. When the arr.push(4) statement is executed, the callback function is called and the output Array changed from [1, 2, 3] to [1, 2, 3, 4] is displayed.

For more information on the $watch function, see the AngularJS documentation.

Edit this code on GitHub