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>
也能输出正确结果