angularJs——利用深拷贝angular.copy()实现取消编辑功能（编辑前保存之前数据，取消后恢复原始数据）

参考：https://www.it1352.com/200163.html

　　　https://blog.csdn.net/Sourcecode_poet/article/details/53509856?depth_1-utm_source=distribute.pc_relevant.none-task&utm_source=distribute.pc_relevant.none-task

一.  理解深拷贝与浅拷贝：

例：　　

var a=1,b;
b=a;
b++;
console.log("a,"+a);  //a,1
console.log("b,"+b);  //b,1
/////////////////////
var c=[1,2,3],d;
d=c;
d.splice(0,1);
console.log("c,"+c);  //c,[2,3]
console.log("d,"+d);  //d,[2,3]
/////////////////////
 var e={
 name:"Jill",
 age:20
 },f;
 f=e;
 f.name="Donny";
 f.age=32;
 console.log("e,"+angular.toJson(e,true)); //e,{name:Donny,age:32}
 console.log("f,"+angular.toJson(f,true)); //f,{name:Donny,age:32}

　　深拷贝：把一个变量x的值赋给另一个变量y，并修改另一个变量的值y，不会影响前一个变量x的情况。如a和b，引用不同的内存地址，所以改变其中一个的值，并不会影响另一个。
　  浅拷贝：把一个变量x的值赋给另一个变量y，修改后者y的值，同时一起影响了前者x的值的情况。如c和d，e和f。引用同一块内存地址，其中一个变量修改了这个内存地址中的值，另一个变量再次访问这块内存地址时，得到的也是修改后的值。

　　Javascript中基本数据类型变量的相互赋值是使用深拷贝执行的，而像数组和对象这种复杂数据类型，使用的则是浅拷贝。

二. 实例——点击“+”时新增，点击“-”时删除，点击“取消”恢复：

html:

<form id="keywordsForm" name="fieldForm" class="am-form am-form-horizontal">
    <div style=" 100%;">
        <div>
            <div ng-show="keysList.length<1" class="am-form-group am-u-sm-12 am-margin-top line-keyword">
                <div class="am-u-sm-12 am-text-center">
                    <button class="am-btn am-btn-warning" ng-click="addKeyword()" style="color: white; cursor: pointer; margin-top: 2rem;">
                        添加关键字</button></div>
            </div>
            <div ng-show="keysList.length>=1" ng-repeat="data in keysList track by $index" class="am-form-group am-u-sm-12 am-margin-top line-keyword">
                <div class="am-u-sm-12">
                    <label class="am-u-sm-2 am-form-label"><span style="color: red"> *</span>关键字{{$index+1}} :</label>
                    <div class="am-u-sm-8">
                        <select class="am-u-sm-2" style=" 20%;" ng-model="data.ztype" ng-options="m.code as m.value for m in matchways">
                        </select> <input type="text" style=" 80%;" class="am-u-sm-10" placeholder="关键字" ng-model="data.words"
                         data-validation-message="请填写关键字" required />
                    </div>
                    <div class="am-u-sm-2" style="padding-top: 0.6em;">
                        <i ng-show="keysList.length==1||keysList.length==($index+1)" style="color: #ccc;" ng-click="addKeyword()" class="am-icon-sm am-icon-plus-circle pointer am-margin-right"></i>
                        <i ng-show="$index>0" style="color: #ccc;" ng-click="deleteKeyword($index)" class="am-icon-sm am-icon-minus-circle pointer"></i>
                    </div>
                </div>
            </div>
        </div>
    </div>
    <div class="form-actions" ng-if="keysList.length>=1" style="text-align: center; padding-bottom: 1%">
        <button type="submit" class="am-btn am-btn-warning" style="color: white; cursor: pointer; margin-top: 2rem;">保&nbsp;存</button>
        &nbsp;&nbsp;&nbsp;&nbsp; <a href="javascript:;" class="am-btn" ng-click="cancelKeywords()" style="color: white;background: buttonface; margin-top: 2rem;">取&nbsp;消</a>
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        <a href="#/list" class="am-btn am-btn-success" style="margin-top: 2rem;">返&nbsp;回</a>
    </div>
</form>

js:

var slist = new Array();
$scope.keysList = new Array();

$http({
    method : 'get',
    params : {},
    data : {},
    url : ***
}).success(function(response, status, headers, config) {
    var rstate = response.result;
    if (rstate == "0") {    
        var _data = response.message;
        $scope.keysList = _data.keysList; //可编辑数据
        slist = angular.copy(_data.keysList); //保存原始数据, 关键语句，进行深拷贝
    }else{
        alert('fail: ' + response.error);
    }
}).error(function(response, status, headers, config) {    
    alert('error: ' + response.error);
});

$scope.matchways = [{code:'1',value:'半匹配'},{code:'2',value:'全匹配'}]; // 关键字匹配类型
//添加关键字
$scope.addKeyword = function(){
    var len =$scope.keysList.length;
    len++;
    $scope.keysList.push({id:'',ztype:'1',words:''});
}
//删除关键字
$scope.deleteKeyword = function(i){
    $scope.keysList.splice(i,1);
    $scope.$digest();
}

$scope.cancelKeywords = function(){
    if(slist.length >= 1){
        $scope.keysList = angular.copy(slist);//关键语句，进行深拷贝
    }else{
        $scope.keysList = [];
    }
}