Angularjs 双向绑定时字符串的转换成数字类型的问题

2019-11-19 16:21:23

字体：大中小

来源：转载

供稿：网友

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>