Angularjs 双向绑定时字符串的转换成数字类型的问题

更新时间：2020-05-17 14:36:01 作者：startmvc

问题：<!DOCTYPEhtml><html><head><metacharset="utf-8"><scriptsrc="http://cdn.static.runoob.

问题：


<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://cdn.static.runoob.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>
<div ng-app="myApp">
<p ng-controller = "myContrl">结果为 <span ng-bind="" ></span>
<input type="text" ng-model="first">{{first+second}}
 </p>
</div>
<script>
 var app = angular.module("myApp",[]);
 app.controller("myContrl",function($scope){
 $scope.first = 5;
 $scope.second =10;
 });
</script>
</body>
</html>

显示结果为

但是，我要是输入50，想要结果为60

因为这个是字符串类型需要转换成数字类型

解决方法：


<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://cdn.static.runoob.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>
<div ng-app="myApp">
<p ng-controller = "myContrl">结果为 <span ng-bind="" ></span>
<input type="text" ng-model="first">{{first *1+second*1}}
 </p>
</div>
<script>
 var app = angular.module("myApp",[]);
 app.controller("myContrl",function($scope){
 $scope.first = 5;
 $scope.second =10;
 });
</script>
</body>
</html>

显示即可正常即是在 {{first *1+second*1}}显示的时候，转换了一下

或者，启用事件监听


<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://cdn.static.runoob.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>
<div ng-app="myApp">
<p ng-controller = "myContrl">结果为 <span ng-bind="" ></span>
<input type="text" ng-model="first">{{total}}
 </p>
</div>
<script>
 var app = angular.module("myApp",[]);
 app.controller("myContrl",function($scope){
 $scope.first = 5;
 $scope.second =10;
 $scope.total = parseInt($scope.first)+parseInt($scope.second);
 $scope.$watch(function(){
 return $scope.first;
 },function(newValue,oldValue){
 if(newValue != oldValue){
 $scope.total = parseInt($scope.first)+parseInt($scope.second);
 }
 });
 });
</script>
</body>
</html>