JavaEE——SpringMVC（8）--处理 JSON：使用 HttpMessageConverter 可做下载
ajax $.ajax()方法详解
使用@ResponseBody注解
从后台获取List<Blog> 传递给前端。并解析
@RequestMapping(value = "/testJson", method = RequestMethod.POST)
public @ResponseBody List<Blog> testJson(HttpServletRequest request){
String id = request.getParameter( "id" );
Integer userId = Integer.valueOf( id );
List<Blog> blog = blogService.findAllBlogByUserId( userId );
/*JSONArray jsonArray = JSONArray.fromObject(blog);*/
/*JSONObject jsonObject = JSONObject.fromObject( blog );*/
return blog;
}
前端将获取到的List数据解析为想要的格式
可使用JavaScript JSON.stringify() 来进行
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body>
<p id="demo"></p>
<script>
var str = {"name":"菜鸟教程", "site":"http://www.runoob.com"}
str_pretty1 = JSON.stringify(str)
document.write( "只有一个参数情况：" );
document.write( "<br>" );
document.write("<pre>" + str_pretty1 + "</pre>" );
document.write( "<br>" );
str_pretty2 = JSON.stringify(str, null, 4) //使用四个空格缩进
document.write( "使用参数情况：" );
document.write( "<br>" );
document.write("<pre>" + str_pretty2 + "</pre>" ); // pre 用于格式化输出
</script>
</body>
</html>
输出结果
只有一个参数情况：
{"name":"菜鸟教程","site":"http://www.runoob.com"}
使用参数情况：
{
"name": "菜鸟教程",
"site": "http://www.runoob.com"
}
<button id="blogType">test Json</button>
<script>
document.getElementById('blogType').addEventListener('click', function () {
var userId = <%--${sessionScope.user.id};--%>
$.ajax({
type: "post",
url: "/blogType/allBlogType",
data: {id:JSON.stringify(userId)},
dataType: "json",
// contentType: "application/json",
success: function(data){
$.each(data, function(i, item){
var json1 = JSON.stringify(item, null, 4);
console.log(json1);
$.each(item, function(j, val){
});
});
}
});
}, false)
</script>
在Controller处
@Controller
@RequestMapping("/blogType")
public class BlogTypeController {
@Autowired
BlogTypeService blogTypeService;
@RequestMapping(value = "/allBlogType")
public @ResponseBody List<BlogType> allBlogType(HttpServletRequest request){
String id = request.getParameter( "id" );
Integer userId = Integer.parseInt(id);
List<BlogType> blog = blogTypeService.allBlogType( userId );
for(BlogType i : blog){
System.out.println(i);
}
return blog;
}
}