Golang路由参数解析技巧分享

package main

import (
    "net/http"
    "regexp"
    "strconv"
    "fmt"
)

func userHandler(w http.ResponseWriter, r *http.Request) {
    re := regexp.MustCompile(`^/user/(\d+)$`)
    matches := re.FindStringSubmatch(r.URL.Path)
    
    if len(matches) > 1 {
        id, _ := strconv.Atoi(matches[1])
        fmt.Fprintf(w, "用户ID: %d", id)
        return
    }
    http.NotFound(w, r)
}

func main() {
    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        if r.URL.Path == "/" {
            fmt.Fprintf(w, "首页")
            return
        }
        userHandler(w, r)
    })
    http.ListenAndServe(":8080", nil)
}

package main

import (
    "github.com/gin-gonic/gin"
)

func main() {
    r := gin.Default()

    // 解析单个参数 :id
    r.GET("/post/:id", func(c *gin.Context) {
        id := c.Param("id")
        c.JSON(200, gin.H{
            "id": id,
        })
    })

    // 解析通配符参数
    r.GET("/file/*filepath", func(c *gin.Context) {
        path := c.Param("filepath")
        c.String(200, "文件路径: %s", path)
    })

    r.Run(":8080")
}

package main

import (
    "github.com/labstack/echo/v4"
    "net/http"
)

func getUser(c echo.Context) error {
    id := c.Param("id")
    return c.String(http.StatusOK, "用户ID: "+id)
}

func main() {
    e := echo.New()
    e.GET("/user/:id", getUser)
    e.Start(":8080")
}

// GET /search?q=golang&page=1
q := c.Query("q")     // 获取查询关键字
page := c.DefaultQuery("page", "1") // 带默认值

// POST 表单提交
username := c.FormValue("username")