How do I ignore the initial load when watching model changes in AngularJS?

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The first time the listener is called, the old value and the new value will be identical. So just do this:

$scope.$watch('fieldcontainer', function(newValue, oldValue) {
  if (newValue !== oldValue) {
    // do whatever you were going to do
  }
});

This is actually the way the Angular docs recommend handling it:

After a watcher is registered with the scope, the listener fn is called asynchronously (via $evalAsync) to initialize the watcher. In rare cases, this is undesirable because the listener is called when the result of watchExpression didn’t change. To detect this scenario within the listener fn, you can compare the newVal and oldVal. If these two values are identical (===) then the listener was called due to initialization

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