angular提供了一個可以復制對象的api——copy(source,destination)，它會對source對象執行深拷貝。
使用時需要注意下面幾點：
- 如果只有一個參數（沒有指定拷貝的對象），則返回一個拷貝對象
- 如果指定了destination,則會深拷貝對象復制給destination
- 如果source是null或者undefined，那么會直接返回source
- 如果source就是desitination，那么會報錯。
下面看看使用樣例：
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://apps.bdimg.com/libs/angular.js/1.2.16/angular.min.js"></script>
</head>
<body ng-app="copyExample">
<div ng-controller="ExampleController">
<form novalidate class="simple-form">
Name: <input type="text" ng-model="user.name" /><br />
E-mail: <input type="email" ng-model="user.email" /><br />
Gender:
<input type="radio" ng-model="user.gender" value="male" />
male
<input type="radio" ng-model="user.gender" value="female" />
female
<br />
<button ng-click="reset()">RESET</button>
<button ng-click="update(user)">SAVE</button>
</form>
<pre>form = {{user | json}}</pre>
<pre>master = {{master | json}}</pre>
</div>
<script>
angular.module('copyExample', [])
.controller('ExampleController', ['$scope', function($scope) {
$scope.master= {};
var test1;
console.log(angular.copy(test1));//undefined
var test3=null;
console.log(angular.copy(test2));//undefined
var test2 = "a";
// console.log(angular.copy(test2,test2));//error!!
$scope.update = function(user) {
// Example with 1 argument
$scope.master= angular.copy(user);
};
$scope.reset = function() {
// Example with 2 arguments
angular.copy($scope.master, $scope.user);
console.log($scope.master);
console.log($scope.user);
};
$scope.reset();
}]);
</script>
</body>
</html>
