Cannot get the current value returned by $http.get when setting $scope variable, only the previous value

Question

I have an angular view that has a table of rows consisting of a select list and an text box. When a select list index is changed, I need to update the corresponding text box on the same row with a lookup value from the database. I am using ng-Change on the select list to call a $scope function that utilizes $http.get to make the call through an ActionMethod. I have tried this in a million ways, and finally was able to extract a value from the $http.get function by assigning it to a scope variable, but I only ever get the value of the previous lookup triggered by the selected index change, not the current one. How can I get a value real-time? I understand it is asynchronous, so I know the nature of the problem. How do I work around it? Current state of my .js:

$scope.EntityId = null; 
$scope.EntityNameChanged = function (item, block) {
    for (var i = 0; i < block.length; i++)
    {
        if (item.Value == block[i].Name.Value) {
            $scope.GetEntityId(item.Value);
            block[i].Id = $scope.EntityId;
        }
    } 
} 
$scope.GetEntityId = function(name) {
    $http.get("EntityId", { params: { EntityName: name } }).then(function success(response) {
        $scope.EntityId = response.data[0].Value;
    }); 
};

Answer 1

The GetEntityID function should return a promise

function GetEntityId(name) {
    //save httpPromise
    var p = $http.get("EntityId", { params: { EntityName: name } });

    //return derived promise
    return p.then(function onSuccess(response) {
        //return chained data
        return response.data[0].Value;
    }); 
};

Then use an IIFE in the for loop.

$scope.EntityNameChanged = function (item, block) {
    for (var i = 0; i < block.length; i++) {
        //USE IIFE to hold value of i
        (function IIFE(i) {
            if (item.Value == block[i].Name.Value) {
                //save promise
                var p = GetEntityId(item.Value);
                //extract value from promise
                p.then(function onSuccess(Value) {
                     block[i].Id = Value;
                });
            }
        })(i); 
    }
} 

Because the onSuccess function gets invoked asynchronously after the for loop completes, an IIFE closure is necessary to preserve the value of i until after the data is returned from the server.

---