angularjs通过ng-change和watch两种方式实现对表单输入改变的监控

angularjs通过ng-change和watch两种方式实现对表单输入改变的监控

直接上练习代码

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title></title>
</head>
<body ng-app="myApp" ng-controller="myContro">
    <div>
        <h1>ng-change指令</h1>
        ng-change指令，当表单输入发生改变时，会触发该事件<br />
        <div>
            姓名：<input type="text" id="name1" ng-model="user.name"
                placeholder="请输入姓名" ng-change="inputChange()" />
        </div>
        <div>
            年龄：<input type="number" ng-model="user.age"
                placeholder="请输入年龄" ng-change="inputChange()" />
        </div>
        <div>{{user.message}}</div>
    </div>
    <div>
        <h1>通过监听改变达到和ng-chang一样的效果</h1>
        <div>
            姓名：<input type="text" id="name2" ng-model="user2.name"
                placeholder="请输入姓名" />
        </div>
        <div>
            年龄：<input type="number" ng-model="user2.age"
                placeholder="请输入年龄" />
        </div>
        <div>{{user2.message}}</div>
    </div>
</body>
</html>
<script src="../JS/angular.js"></script>
<script type="text/javascript">
    var app = angular.module("myApp", []);
    app.controller("myContro", function ($scope, $interpolate) {
        $scope.user = {
            name: "",
            age: "",
            message: ""
        };

        $scope.user2 = {
            name: "",
            age: "",
            message: ""
        };

        $scope.messageTemp = "{{name}},您好,您今年{{age}}岁啦！";
        var template = $interpolate($scope.messageTemp);
        $scope.inputChange = function () {
            $scope.user.message = template({ name: $scope.user.name, age: $scope.user.age });
        };

        //// 下面通过watch监听实现ng-change一样的效果
        $scope.$watch("user2.name", function (newValue, oldValue) {
            $scope.getMessage(newValue, oldValue);
        });

        $scope.$watch("user2.age", function (newValue, oldValue) {
            $scope.getMessage(newValue, oldValue);
        });

        $scope.getMessage = function (value1, value2) {
            if (value1 != value2) {
                $scope.user2.message = template({ name: $scope.user2.name, age: $scope.user2.age });
            }
        }
    });
</script>