Node.js_后端路由(一)

Node.js_后端路由(一)

路由指的就是我们要针对不同的URL有不同的处理方式。

• JS在处理URL时，req.url中的pathname就是用户请求的路径，query就是get请求时用户传递的参数。所以说pathname就是路由的核心。

  req.url.png

• 读取服务端的文件时，需要通过content-type反馈给客户端，告诉它读取的文件是什么类型的。

  例如：

  res.writeHead(200, { "contentType": "text/html;charset=utf8" });

  res.writeHead(200, { "content-type": "application/x-javascript;charset=utf8" });

  res.writeHead(200, { "content-Type": "application/JSON;charset=utf-8" })

• 请求图片时，使用正则表达式的子匹配项来区分请求的图片名和后缀。

  if (/\/img\/(.*)\.(jpg|png|gif)/.test(pathname)) {
      fs.readFile(path.join(__dirname, "./public/img/" + RegExp.$1 + "." + RegExp.$2), (err, data) => {
          res.writeHead(200, { "content-type": "image/" + RegExp.$2 });
          res.end(data);
      })
  

• 测试数据存放在json文件中

  json数据.png

• 登录注册的node代码

const http = require("http");
const path = require("path");
const fs = require("fs");
const url = require("url");
const server = http.createServer((req, res) => {
    // console.log(url.parse(req.url, true))
    const { pathname, query } = url.parse(req.url, true);

    if (pathname === "/") {

        fs.readFile(path.join(__dirname, "./public/index.html"), (err, data) => {
            res.writeHead(200, { "contentType": "text/html;charset=utf8" });
            res.end(data);
        })

    } else if (pathname === "/order") {
        fs.readFile(path.join(__dirname, "./public/html/order.html"), (err, data) => {
            res.writeHead(200, { "contentType": "text/html;charset=utf8" });
            res.end(data);
        })
    } else if (pathname === "/list") {
        fs.readFile(path.join(__dirname, "./public/html/list.html"), (err, data) => {
            res.writeHead(200, { "contentType": "text/html;charset=utf8" });
            res.end(data);
        })
    } else if (/\/css\/(.*)\.css/.test(pathname)) {
        fs.readFile(path.join(__dirname, "./public/css/" + RegExp.$1 + ".css"), (err, data) => {
            res.writeHead(200, { "content-type": "text/css;charset=utf8" });
            res.end(data);
        })
    } else if (/\/js\/(.*)\.js/.test(pathname)) {
        fs.readFile(path.join(__dirname, "./public/js/" + RegExp.$1 + ".js"), (err, data) => {
            res.writeHead(200, { "content-type": "application/x-javascript;charset=utf8" });
            res.end(data);
        })
    } else if (/\/img\/(.*)\.(jpg|png|gif)/.test(pathname)) {
        fs.readFile(path.join(__dirname, "./public/img/" + RegExp.$1 + "." + RegExp.$2), (err, data) => {
            res.writeHead(200, { "content-type": "image/" + RegExp.$2 });
            res.end(data);
        })
    } else if (pathname === "/users/register") {
        let { username, password } = query;
        fs.readFile(path.join(__dirname, "./public/data/user.json"), (err, data) => {
            let userData = JSON.parse(data.toString());
            var bStop = true;

            for (var i = 0; i < userData.data.length; i++) {
                if (userData.data[i].username === username) {
                    bStop = false;
                    break;
                }
            }
            if (bStop) {
                userData.data.push({ username, password });
                fs.writeFile(path.join(__dirname, "./public/data/user.json"), JSON.stringify(userData), (err) => {
                    if (!err) {
                        res.writeHead(200, { "content-Type": "application/json;charset=utf-8" })
                        res.end(JSON.stringify({
                            code: 200,
                            errMsg: "",
                            data: {
                                code: 1,
                                info: "注册成功"
                            }
                        }))
                    }
                })
            } else {
                res.writeHead(200, { "content-Type": "application/json;charset=utf-8" })
                res.end(JSON.stringify({
                    code: 200,
                    errMsg: "",
                    data: {
                        code: 0,
                        info: "用户名重复"
                    }
                }))
            }
        })
    }
    else if (pathname === "/users/login") {
        let { username, password } = query;
        var resObj = {
            code: 200,
            errMsg: ""
        }
        fs.readFile(path.join(__dirname, "./public/data/user.json"), (err, data) => {
            let userData = JSON.parse(data.toString());
            var loginStop = 0;
            for (var i = 0; i < userData.data.length; i++) {
                if (userData.data[i].username === username) {
                    loginStop = 2;
                    if (userData.data[i].password === password) {
                        loginStop = 1;
                        break;
                    }
                }
            }
            res.writeHead(200, { "content-Type": "application/JSON;charset=utf-8" })
            if (loginStop === 1) {
                // userData.data.push({ username, password });
                resObj.data = {
                    code: 1,
                    info: "登录成功，跳转主页！"
                }
            } else if (loginStop === 2) {
                resObj.data = {
                    code: 0,
                    info: "用户密码错误！"
                }
            } else {
                resObj.data = {
                    code: 0,
                    info: "用户不存在！"
                }
            }
            res.end(JSON.stringify(resObj))
        })
    }
})

server.listen(9000, () => {
    console.log("server address:127.0.0.1:9000")
})