Question

尝试将一个变量复制到另一个变量时遇到错误

var app = angular.module('myApp', []);
  app.controller('myCtrl', function($scope, $http) {
    $scope.myWelcome = "Welcome"
    var vm = this,
        parent = $scope.summary,
        results = $scope.results,
        matches = {
            "value":"John"
        };
    parent.def = angular.copy(matches);
    $scope.myWelcome =  parent.def;
});

//面对此错误，请有人指导：

   TypeError: Cannot set property 'def' of undefined
    at Object.<anonymous> (<anonymous>:11:14)
    at Object.invoke (angular.js:5106)
    at O.instance (angular.js:11076)
    at p (angular.js:9939)
    at f (angular.js:9248)
    at angular.js:9113
    at angular.js:1960
    at m.$eval (angular.js:18542)

Answer 1

在这一行：parent.def = angular.copy(matches);，parent等于$scope.summary。

因此，您尝试做等效于$scope.summary.def = angular.copy(matches)的事情。由于$scope.summary未定义，因此会引发错误。

您可以通过首先将$scope.summary定义为一个空对象$scope.summary = {}来解决此问题。

无法在Angular JS中设置未定义的属性“ $ scope变量”

1 个答案: