Spring MVC 传参类型 ! 非常实用都懂了吗？一起学习吧技术頭條網

Spring MVC 传参类型 ! 非常实用都懂了吗？一起学习吧

参数

1.@RequestParam

主要来是于URL，如 https://www.toutiao.com/c/user/4142556860923036/#mid=1656249383812099 小编的主页地址，就是这种参数。

2.@RequestBody

主要来自表单信息，通过POST的方式把表单的信息传到后台。

3.@RequestHeader

求请的表单头。一般用来放浏览器信息，cookies等信息。

代码实例

下面通过一个实例来说明Spring MVC 参数的设置，网络传输抓包，以及前端的调用。

服务层代码

<code>import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.sql.SQLException;
import java.util.List;

@CrossOrigin
@RestController
@Api(value = "Test", description = "Test")
public class Test { 

    
    @ApiOperation(value = "参数测试")
    @RequestMapping(path = "test/paramTest", method = RequestMethod.POST)
    public String paramTest(
            @RequestParam String OperateType ,
            @RequestBody InputClass inp,
            @RequestHeader String  token
    ) {
        return "Richy's Test";
    }
}/<code>

实体层

<code>package rui.tools.service.Test;

public class InputClass {
   private   String attr1;
   private  String attr2;

    public String getAttr1() {
        return attr1;
    }

    public void setAttr1(String attr1) {
        this.attr1 = attr1;
    }

    public String getAttr2() {
        return attr2;
    }

    public void setAttr2(String attr2) {
        this.attr2 = attr2;
    }
}
/<code>

前端测试

<code> function f_c() {
            var url = "http://localhost:8080/test/paramTest?OperateType=add";
            var opt = {
                attr1: "a",
                attr2: "b", 

            };
            $.ajax({
                type: "POST",
                url: url,
                headers: {
                  token:'key'
                },
                data: JSON.stringify(opt),
                contentType: "application/json",
                success: function (data) {
                    alert(data)
                },
                error: function (data) { alert("error"); }
            });
        }/<code>

浏览器网络分析

@RequestParam对应的是URL的参数

@RequestBody对应的是Form 的值

@RequestHeader 对应是 Head的参数

如下图所示

浏览器网络分析

补充

因为是前后端分离，需要注意跨域的处理

本例子使用后台设置header允许跨域访问

代码如下：

<code>import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class WebFillter implements Filter {
    public void destroy() {
    }

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) res;
        String originHeader = request.getHeader("Origin");
        response.setHeader("Access-Control-Allow-Origin", originHeader);
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
        response.setHeader("Access-Control-Max-Age", "0");
        response.setHeader("Access-Control-Allow-Headers", "Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With,userId,token");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("XDomainRequestAllowed", "1");
        response.setHeader("XDomainRequestAllowed", "1");
        chain.doFilter(request, response);
    }
    public void init(FilterConfig arg0) throws ServletException {

    }
}/<code>