How to replace JSON array value withe new one using Angular.js/javascript

Question

I need to replace JSON array value using Angular.js/Javascript. this is my code below.

Suppose i pushed some value to an object like below.

for(var i=0;i<mondayarr.length;i++){
    $scope.days[0].answers.push({
                category:{'value':mondayarr[i].cat_id},
                subcategory: null,
                comment: response.data[i].comment,
  })
  $scope.setSubcatag(0);
}

inside the loop i pushed some value into the array and called a function with the value. this is the subcategory is assigned to null.

$scope.setSubcatag=function(index){
   $scope.days[index].answers.push({
            subcategory:{'value':2}
  })
}

In the above section i am replacing subcategory value null to some value but its not replacing. please help me.

Answer 1

You are pushing one more value to the array, instead replace it, but you have to know the answer's index as well.

$scope.setSubcatag=function(index)
{
   $scope.days[index].answers[whichAnswerIndex].subcategory = {'value':subcat_id};
}

Answer 2

you are pushing a new object to the days[index].answer where you should assign the subcategory. in order to do so you need to add a new argument to the setSubcatag.

$scope.setSubcatag=function(index,answerId)
{
   $scope.days[index].answers[answerId].subcategory = {'value':2};
}

and in the base

for(var i=0;i<mondayarr.length;i++){
    $scope.days[0].answers.push({
                category:{'value':mondayarr[i].cat_id},
                subcategory: null,
                comment: response.data[i].comment,
  })
  $scope.setSubcatag(0);
}