如果workpieceFlow中的workpieces_id === workpieceList.id，就把workpieceFlow中的num取出來相加，最后賦值給workpieceList的realnum屬性，請問一下大家有什么方法推薦么？我是加了一個全局變量。。。var realNum = 0;_.each($scope.workpieceFlow, function(item){item.workpieces_id === $scope.workpieceList.id && (realNum += item.num);});$scope.workpieceList.realNum = realNum;