AngularJS服务和并发访问全局变量

Question

I use two asynchronous web services. I have to make time for adding each object returned in responses. The target data is same ($scope.time is a global variable). I fear that when time = time + X some time or crushed.

$scope.time = 0;

$scope.elemAs = [];
$scope.loadElemA = function(nb) {
    ElemAService.query({nb: nb}, function(result) {
        $scope.elemAs = result;
        for (var index = 0; index < $scope.elemAs.length; index++) {
            $scope.time = $scope.time + $scope.elemAs[index].time;
        }
    });
};
$scope.loadElemA(2);

$scope.elemBs = [];
$scope.loadElemB = function(nb) {
    ElemBService.query({nb: nb}, function(result) {
        $scope.elemBs = result;
        for (var index = 0; index < $scope.elemBs.length; index++) {
            $scope.time = $scope.time + $scope.elemBs[index].time;
        }
    });
};
$scope.loadElemB(3);

console.log($scope.time);

In my results , I am not sure to get $scope.time = A0.time + A1.time + B0.time + B1.time + B2.time ?

In java I use a synchronized methode to do a add by any threads, but in javascript I do not know how to do.

Example 1:

(2) = > $scope.time = $scope.time + $scope.elemAs[0].time; (2)

(4) = > $scope.time = $scope.time + $scope.elemAs[1].time; (2)

(6) = > $scope.time = $scope.time + $scope.elemBs[0].time; (2)

(8) = > $scope.time = $scope.time + $scope.elemBs[1].time; (2)

( 10 ) = > $scope.time = $scope.time + $scope.elemBs[2].time; (2)

Example 2:

(2) = > $scope.time = $scope.time + $scope.elemAs[0].time; (2)

(4) = > $scope.time = $scope.time + $scope.elemBs[0].time; (2)

(6) = > $scope.time = $scope.time + $scope.elemBs[1].time; (2)

(8) = > $scope.time = $scope.time + $scope.elemAs[1].time; (2)

( 10 ) = > $scope.time = $scope.time + $scope.elemBs[2].time; (2)

Example 3:

(2) = > $scope.time = $scope.time + $scope.elemAs[0].time; (2)

(4) = > $scope.time = $scope.time + $scope.elemBs[0].time; (2)

(6) = > $scope.time = $scope.time + $scope.elemBs[1].time; (2) same time $scope.time = $scope.time + $scope.elemAs[1].time; (2)

( 8 ) = > $scope.time = $scope.time + $scope.elemBs[2].time; (2)

Answer 1

I have the answer at my question. I had a big loop in each callback. The javascript have only one thread for all callbacks.

$scope.time = 0;

$scope.elemAs = [];
$scope.loadElemA = function(nb) {
    ElemAService.query({nb: nb}, function(result) {
        $scope.elemAs = result;
        for (var index = 0; index < $scope.elemAs.length; index++) {
            $scope.time = $scope.time + $scope.elemAs[index].time;
            for(var kk = 0; kk < 10000; kk++){
                console.log("A");
            }
        }
    });
};
$scope.loadElemA(2);

$scope.elemBs = [];
$scope.loadElemB = function(nb) {
    ElemBService.query({nb: nb}, function(result) {
        $scope.elemBs = result;
        for (var index = 0; index < $scope.elemBs.length; index++) {
            $scope.time = $scope.time + $scope.elemBs[index].time;
            for(var kk = 0; kk < 10000; kk++){
                console.log("B");
            }
        }
    });
};
$scope.loadElemB(3);

console.log($scope.time);

with this test, I see that I have 10.000 A and 10.000 B or 10.000 B and 10.000 A. I have never a mix of A and B ( AAABAABBA ... )

My code is good, I have no problem doing my additions in my callbacks