Node express框架 request对象的query和params属性的区别

浅浅的花香味﹌ 2022-01-10 02:19 248阅读 0赞

## 区别 ##

*  后端方法：`app.get("/deleteUser/:id", function(req, res) {...});`
 *  请求URL：`http://localhost:8080/deleteUser/2?user=张三&passwd=zhangsan`
 *  页面结果：

req.params: {
    	"user": "张三",
    	"passwd": "zhangsan"
    }
    req.query: {
    	"id": "2"
    }

即：`req.params`为查询参数对。而`req.query`是对应于后端代码中`:名称`的部分。

## demo ##

var fs = require("fs");
    var express = require("express");
    var app = express();
    
    app.get("/deleteUser/:id", function (req, resp) {
        var query = JSON.stringify(req.query, null, "\t");
        var params = JSON.stringify(req.params, null, "\t");
        
        console.log("query:", query);
        console.log("params:", params);
    
        resp.setHeader("Content-Type", "text/json; charset=utf8");
        resp.write("req.params: " + query + "\n");
        resp.end("req.query: " + params);
    });
    
    app.listen(8080);

运行后访问：`http://localhost:8080/deleteUser/2?user=张三&passwd=zhangsan`

结果如图：  
![在这里插入图片描述][20190620210004300.png]  
即数据为：

req.params: {
    	"user": "张三",
    	"passwd": "zhangsan"
    }
    req.query: {
    	"id": "2"
    }

**NOTE**: 访问URI中的`/deleteUser/2`不应该是`/deleteUser/:2`。  
否则`req.query`属性的`id`值为`:2`而非`2`。  
(后端代码中`app.get(path, callback)`的`path`值为`/deleteUser/:id`，有一个冒号)

## Additional ##

`request`还有另外的属性，如`url, baseUrl, originalUrl`。  
`http://localhost:8080/deleteUser/2?user=%E5%BC%A0%E4%B8%89&passwd=zhangsan`

req.params:  { id: '2' }
    req.query:  { user: '张三', passwd: 'zhangsan' }
    req.url:  /deleteUser/2?user=%E5%BC%A0%E4%B8%89&passwd=zhangsan
    req.baseUrl:  
    req.originalUrl:  /deleteUser/2?user=%E5%BC%A0%E4%B8%89&passwd=zhangsan

[20190620210004300.png]: /images/20220109/3b1c9e9cf8d344a2872f78437837a144.png