Three kinds of response AJax

AJax response

      1. Ordinary text (character string) 
      resp.getWriter () Print ( "Hello");

  //2.JSON give a set of front page format when using plain text transmission or transmission String object when it is time to introduce JSON
   background servlet code

    Student stu = new Student (16, " fifty-five", 55); 
          // need to import-2.2.4.jar jar package GSON Gson GSON new new Gson = (); 
        String S = gson.toJson (STU);　　 
        // { "id": 16, "name ": " fifty-five", "age": 55} is converted to this format 
        System.out.println (S); 
        . resp.getWriter () Print (S);
       

　　

   Reception Code

text = xhr.responseText var; 
// passed in 
the console.log (text) 
the console.log (typeof text) // String Type

"{" id ": 16, " name ":" fifty-five "," Age ": 55}" 

// still be converted to JSON type method using JSON

var stu= JSON.parse(text); 

console.log(stu.id)
 console.log(typeof stu) //object类型

　　

[3] XML format (Learn)

var = xhr.responseXML DOC;
var name = doc.getElementsByTagName ( "name") [0] .innerHTML;