Check if a complex scope variable was modified in Angular JS

Question

I have a Complex scope variable, something like the following.

$scope.ComplexVariable={
      PrimaryObjOne:{
         SecondaryOne:'',
         SecondaryTwo:''
      },
      PrimaryObjTwo:{
         SecondaryOne:'',
         SecondaryTwo:''
      }
}

Is there any clean way to check if any of the properties(at the secondary level in my example) associated with this object were modified. Adding a $watch against each property would work, but I was wondering if there was a cleaner way to do this.

score 0 · Accepted Answer · answered Dec 09 '15 at 18:08

0

$scope.$watch("ComplexVariable", function (oldVal, newVal) {
}, true);

The true at the end will watch the entire object for any changes.

answered Dec 09 '15 at 18:08

Scottie

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This helps. Thanks!! – Ritwik Sen Dec 09 '15 at 18:13

score 0 · Answer 2 · answered Dec 09 '15 at 18:08

The third argument to $scope.$watch allows you to compare objects using object equality rather than reference equality (which is the default).

function objectChanged() {
  // ...
}

var useObjectEquality = true;

$scope.$watch('ComplexVariable', objectChanged, useObjectEquality);

This makes use of angular.equals rather than == or ===.

Check if a complex scope variable was modified in Angular JS

2 Answers2