让 SpringMVC 接收多个对象的4种方法

jopen 7年前

问题背景:

我要在一个表单里同时一次性提交多名乘客的个人信息到SpringMVC,前端HTML和SpringMVC Controller里该如何处理?

  • 第1种方法:表单提交,以字段数组接收;
  • 第2种方法:表单提交,以BeanListModel接收;
  • 第3种方法:将Json对象序列化成Json字符串提交,以List接收;
  • 第4种方法:将表单对象序列化成Json字符串提交,以List接收;
    第4种方法其实是第3种方法的升级,就是将表单转成Json对象,再转成Json字符串提交;
    然而,第4种方法还不支持含有多选控件表单的提交,故应该还有第5种加强版的方法。

以上4种方法都共用同一个User实体类,代码如下:

public class User {        private Integer id;      private String name;      private String pwd;        @Override      public String toString() {          return "User{" +                  "id=" + id +                  ", name='" + name + '\'' +                  ", pwd='" + pwd + '\'' +                  '}';      }      // .......后面还有getter、setter方法,省略了   }

第1种方法:表单提交,以字段数组接收

HTML代码如下:

    <form action="/user/submitUserList_1" method="post">          ID:<input type="text" name="id"><br/>          Username:<input type="text" name="name"><br/>          Password:<input type="text" name="pwd"><br/><br/>            ID:<input type="text" name="id"><br/>          Username:<input type="text" name="name"><br/>          Password:<input type="text" name="pwd"><br/><br/>          <input type="submit" value="submit">      </form>

Java代码如下:

    @RequestMapping(value = "/submitUserList_1", method ={RequestMethod.POST})      @ResponseBody      public String submitUserList_1(HttpServletResponse response,Integer[] id, String[] name, String[] pwd)                              throws Exception{          String result = "";          if(id == null || id.length <= 0){ return "No any ID.中文"; }          List<User> userList = new ArrayList<User>();          for (int i = 0; i < id.length; i++ ) {              User user = new User();              user.setId(id[i]);              user.setName(name[i]);              user.setPwd(pwd[i]);              userList.add(user);          }          result = this.showUserList(userList);          return result;      }

第2种方法:表单提交,以BeanListModel接收

HTML代码如下:

    <form action="/user/submitUserList_2" method="post">          ID:<input type="text" name="users[0].id"><br/>          Username:<input type="text" name="users[0].name"><br/>          Password:<input type="text" name="users[0].pwd"><br/><br/>            ID:<input type="text" name="users[2].id"><br/>          Username:<input type="text" name="users[2].name"><br/>          Password:<input type="text" name="users[2].pwd"><br/><br/>          <input type="submit" value="Submit">      </form>

Java代码:

除了刚才公用的User类,还要封装一个User的容器类UserModel:

public class UserModel {      private List<User> users;        public List<User> getUsers() {          return users;      }        public void setUsers(List<User> users) {          this.users = users;      }        public UserModel(List<User> users) {          super();          this.users = users;      }        public UserModel() {          super();      }    }

SpringMVC Controller方法:

    @RequestMapping(value = "/submitUserList_2", method ={RequestMethod.POST})      @ResponseBody      public String submitUserList_2(UserModel users)              throws Exception{          String result = "";          List<User> userList = users.getUsers();          if(userList == null || userList.size() <= 0){ return "No any ID.中文"; }          result = this.showUserList(userList);          return result;      }

第3种方法:将Json对象序列化成Json字符串提交,以List接收

HTML代码:

<head>      <title>submitUserList_3</title>      <meta http-equiv="content-type" content="text/html; charset=utf-8">      <script language="JavaScript" src="/js/jquery.min.js" ></script>      <script language="JavaScript" src="/js/jquery.json.min.js" ></script>      <script type="text/javascript" language="JavaScript">          function submitUserList_3() {alert("ok");              var customerArray = new Array();              customerArray.push({id: "1", name: "李四", pwd: "123"});              customerArray.push({id: "2", name: "张三", pwd: "332"});              $.ajax({                  url: "/user/submitUserList_3",                  type: "POST",                  contentType : 'application/json;charset=utf-8', //设置请求头信息                  dataType:"json",                  //data: JSON.stringify(customerArray),    //将Json对象序列化成Json字符串,JSON.stringify()原生态方法                  data: $.toJSON(customerArray),            //将Json对象序列化成Json字符串,toJSON()需要引用jquery.json.min.js                  success: function(data){                      alert(data);                  },                  error: function(res){                      alert(res.responseText);                  }              });          }      </script>  </head>    <body>      <h1>submitUserList_3</h1>      <input id="submit" type="button" value="Submit" onclick="submitUserList_3();">  </body>

Java代码:

    @RequestMapping(value = "/submitUserList_3", method ={RequestMethod.POST})      @ResponseBody      public String submitUserList_3(@RequestBody List<User> users)              throws Exception{          String result = "";          if(users == null || users.size() <= 0){ return "No any ID.中文"; }          result = this.showUserList(users);          return result;      }

第4种方法:将表单对象序列化成Json字符串提交,以List接收

HTML代码:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"          "http://www.w3.org/TR/html4/loose.dtd">  <html>  <head>      <title>submitUserList_4</title>      <meta http-equiv="content-type" content="text/html; charset=utf-8">      <script language="JavaScript" src="/js/jquery.min.js" ></script>      <script type="text/javascript" language="JavaScript">          //将表单序列化成json格式的数据(但不适用于含有控件的表单,例如复选框、多选的select)          (function($){              $.fn.serializeJson = function(){                  var jsonData1 = {};                  var serializeArray = this.serializeArray();                  // 先转换成{"id": ["12","14"], "name": ["aaa","bbb"], "pwd":["pwd1","pwd2"]}这种形式                  $(serializeArray).each(function () {                      if (jsonData1[this.name]) {                          if ($.isArray(jsonData1[this.name])) {                              jsonData1[this.name].push(this.value);                          } else {                              jsonData1[this.name] = [jsonData1[this.name], this.value];                          }                      } else {                          jsonData1[this.name] = this.value;                      }                  });                  // 再转成[{"id": "12", "name": "aaa", "pwd":"pwd1"},{"id": "14", "name": "bb", "pwd":"pwd2"}]的形式                  var vCount = 0;                  // 计算json内部的数组最大长度                  for(var item in jsonData1){                      var tmp = $.isArray(jsonData1[item]) ? jsonData1[item].length : 1;                      vCount = (tmp > vCount) ? tmp : vCount;                  }                    if(vCount > 1) {                      var jsonData2 = new Array();                      for(var i = 0; i < vCount; i++){                          var jsonObj = {};                          for(var item in jsonData1) {                              jsonObj[item] = jsonData1[item][i];                          }                          jsonData2.push(jsonObj);                      }                      return JSON.stringify(jsonData2);                  }else{                      return "[" + JSON.stringify(jsonData1) + "]";                  }              };          })(jQuery);            function submitUserList_4() {alert("ok");              var jsonStr = $("#form1").serializeJson();              //console.log("jsonStr:\r\n" + jsonStr);              //alert(jsonStr);              $.ajax({                  url: "/user/submitUserList_4",                  type: "POST",                  contentType : 'application/json;charset=utf-8', //设置请求头信息                  dataType:"json",                  data: jsonStr,                  success: function(data){                      alert(data);                  },                  error: function(res){                      alert(res.responseText);                  }              });          }      </script>  </head>    <body>      <h1>submitUserList_4</h1>      <form id="form1">          ID:<input type="text" name="id"><br/>          Username:<input type="text" name="name"><br/>          Password:<input type="text" name="pwd"><br/><br/>            ID:<input type="text" name="id"><br/>          Username:<input type="text" name="name"><br/>          Password:<input type="text" name="pwd"><br/><br/>          <input type="button" value="submit" onclick="submitUserList_4();">      </form>  </body>  </html>

Java代码:

    @RequestMapping(value = "/submitUserList_4", method ={RequestMethod.POST})      @ResponseBody      public String submitUserList_4(@RequestBody List<User> users)              throws Exception{          String result = "";          if(users == null || users.size() <= 0){ return "No any ID.中文"; }          result = this.showUserList(users);          return result;      }

总结:

第1、2种方法其实都有一个共同的BUG:假如提交三条记录时,前面两条记录的某些字段不填值的话,在SpringMVC里接收不准确了。而且,每 2种方法在HMTL中需要给name属性添加[下标],如果下标有跨度的话(比如第一组控件下标是0,第二组下标是2),那么SpringMVC里其实的是0到2三个对象的,默认下标是1的那个对象全为null值。
第3、4种方法最实用。

以上方法参考自以下URL:
http://www.cnblogs.com/wsw0515/p/3582627.html
http://www.oschina.net/question/917732_106601
http://jxd-zxf.iteye.com/blog/2072300
http://www.tashan10.com/jquery-jiang-biao-dan-xu-lie-hua-wei-jsondui-xiang/

来源:lutinghuan的博客