AngularJS发起$http.post请求收不到返回的数据，结果为null

解决方案：

1. 配置$httpProvider：

   var myApp = angular.module('app',[]);  
    myApp.config(function($httpProvider){  
   
      $httpProvider.defaults.transformRequest = function(obj){  
        var str = [];  
        for(var p in obj){  
          str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));  
        }  
        return str.join("&");  
      }  
   
      $httpProvider.defaults.headers.post = {  
           'Content-Type': 'application/x-www-form-urlencoded'  
      }  
   
   });  

2. 或者在post中配置:

   $http({  
      method:'post',  
      url:'post.php',  
      data:{name:"aaa",id:1,age:20},  
      headers:{'Content-Type': 'application/x-www-form-urlencoded'},  
      transformRequest: function(obj) {  
        var str = [];  
        for(var p in obj){  
          str.push(encodeURIComponent(p) + "=" + encodeURIComponent(obj[p]));  
        }  
        return str.join("&");  
      }  
   }).success(function(req){  
          console.log(req);  
   })