gin

1.helloworld

package main

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

func main() {
	engine := gin.Default()
	engine.GET("/hello", func(context *gin.Context) {
		context.Writer.Write([]byte("hello"))
	})

	engine.Run(":8090")
}

使用handle处理请求

package main

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

func main() {
	engine := gin.Default()
	engine.Handle("GET", "/hello", func(context *gin.Context) {
		fmt.Println(context.FullPath())
		fmt.Println(context.Request.URL)
		fmt.Println(context.Request.Method)
		context.Writer.WriteString("hello world")
	})

	// 获取GET请求 http://127.0.0.1:8090/demo?name=wanghaha&age=24
	engine.Handle("GET", "/demo", func(context *gin.Context) {
		fmt.Println(context.FullPath())
		name := context.DefaultQuery("name", "wang")
		age := context.Query("age")

		fmt.Println(name, age)
		context.Writer.WriteString(fmt.Sprintf("name:%v, age:%v", name, age))
	})

	// 获取POST请求
	engine.Handle("POST", "/demoPost", func(context *gin.Context) {
		fmt.Println(context.FullPath())
		username := context.PostForm("username")
		password := context.PostForm("password")

		fmt.Println("username:", username)
		fmt.Println("password:", password)

		context.Writer.WriteString(fmt.Sprintf("username: %v, password: %v", username, password))
	})

	err := engine.Run(":8090")
	if err != nil {
		log.Fatal(err)
	}
}

直接使用gin封装后的GET, POST, DELETE等

package main

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

func main() {
	engine := gin.Default()
	engine.GET("/hello", func(context *gin.Context) {
		name := context.Query("name")
		context.Writer.WriteString(name)
	})

	engine.POST("/login", func(context *gin.Context) {
		username := context.PostForm("username")
		password := context.PostForm("password")

		if username == "admin" && password == "111111" {
			context.Writer.WriteString("ok")
		} else {
			context.Writer.WriteString("username or password error")
		}
	})
	
	engine.DELETE("/delete_user/:id", func(context *gin.Context) {
		id := context.Param("id")
		context.Writer.WriteString(id)
	})

	engine.Run(":8090")
}

参数绑定 GET请求

http://127.0.0.1:8090/hello?name=wanghaha&age=24&sex=1

package main

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

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

	// 参数绑定GET请求
	engine.GET("/hello", func(context *gin.Context) {
		var user User
		err := context.ShouldBindQuery(&user)
		if err != nil {
			log.Fatal(err)
		}

		fmt.Println(user.Name)
		fmt.Println(user.Age)
		fmt.Println(user.Sex)
		context.Writer.WriteString(user.Name)
	})

	err := engine.Run(":8090")
	if err != nil {
		log.Fatal(err)
	}
}

type User struct{
	Name string `form:"name"`
	Age int `form:"age"`
	Sex int `form:"sex"`
}

参数绑定 POST请求

package main

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

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

	// 参数绑定POST请求
	engine.POST("/testPost", func(context *gin.Context) {
		var user User
		err := context.ShouldBind(&user)
		if err != nil {
			log.Fatal(err)
		}

		fmt.Println(user.Name)
		fmt.Println(user.Age)
		fmt.Println(user.Sex)
		context.Writer.WriteString(user.Name)
	})

	err := engine.Run(":8090")
	if err != nil {
		log.Fatal(err)
	}
}

type User struct{
	Name string `form:"name"`
	Age int `form:"age"`
	Sex int `form:"sex"`
}

绑定JSON格式数据

package main

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

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

	// 参数绑定POST, JSON格式请求
	engine.POST("/testPost", func(context *gin.Context) {
		var user User
		err := context.BindJSON(&user)
		if err != nil {
			log.Fatal(err)
		}

		fmt.Println(user.Name)
		fmt.Println(user.Age)
		fmt.Println(user.Sex)
		context.Writer.WriteString(user.Name)
	})

	err := engine.Run(":8090")
	if err != nil {
		log.Fatal(err)
	}
}

type User struct{
	Name string `form:"name"`
	Age int `form:"age"`
	Sex int `form:"sex"`
}

返回JSON数据

package main

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

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

	// 返回JSON格式数据，第一种方式
	engine.GET("/", func(context *gin.Context) {
		context.JSON(200, map[string]interface{}{
			"code": 0,
			"msg": "ok",
			"data": map[string]interface{}{
				"value": 25,
			},
		})
	})

	// 返回JSON格式数据，第二种方式
	engine.GET("/t1", func(context *gin.Context) {
		context.JSON(http.StatusOK, gin.H{
			"code": 0,
			"msg": "ok",
		})
	})

	// 返回JSON格式数据，第三种方式
	engine.GET("/t2", func(context *gin.Context) {
		context.JSON(200, Response{
			Code: 0,
			Msg:  "ok",
			Data: nil,
		})
	})

	engine.Run(":8090")
}

// 自定义响应结构体
type Response struct{
	Code int
	Msg string
	Data interface{}
}

返回html&加载静态文件

package main

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

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

	// 加载模板文件
	engine.LoadHTMLGlob("./templates/*")

	// 加载静态文件目录
	engine.Static("/static", "./static")

	engine.GET("/", func(context *gin.Context) {
		context.HTML(200, "index.html", nil)
	})

	engine.GET("/home", func(context *gin.Context) {
		context.HTML(http.StatusOK, "home.html", gin.H{
			"title": "home page",
			"message": "hello world",
		})
	})

	engine.Run(":8090")
}

templates/index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>index</title>
</head>
<body>
    <h1>index page</h1>
    <img src="/static/feng.jpg" alt="">
</body>
</html>

templates/home.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>{{.title}}</title>
</head>
<body>
    <h1>message: {{.message}}</h1>
</body>
</html>

路由组

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
)

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

	// 路由分组
	api := engine.Group("/api")

	// 获取用户接口
	api.GET("/get_user/:id", func(context *gin.Context) {
		context.JSON(http.StatusOK, gin.H{"id": context.Param("id")})
	})

	// 添加用户接口
	api.POST("/add_user", func(context *gin.Context) {
		type User struct {
			Name string `form:"name"`
			Age int `form:"age"`
		}
		var user User
		if err := context.ShouldBind(&user); err != nil {
			log.Fatal(err)
		}

		fmt.Printf("name: %v, age:%v\n", user.Name, user.Age)
		context.JSON(http.StatusOK, gin.H{
			"code": 0,
			"msg": "ok",
		})
	})

	// 删除用户接口
	api.DELETE("/delete_user/:id", func(context *gin.Context) {
		context.JSON(http.StatusOK, gin.H{"id": context.Param("id")})
	})

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err)
	}
}

试图函数另一种写法

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
)

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

	// 路由分组
	api := engine.Group("/api")
	{
		// 获取用户接口
		api.GET("/get_user/:id", GetUser)

		// 添加用户接口
		api.POST("/add_user", AddUser)

		// 删除用户接口
		api.DELETE("/delete_user/:id", DeleteUser)
	}

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err)
	}
}

// 获取用户
func GetUser(context *gin.Context) {
	context.JSON(http.StatusOK, gin.H{"id": context.Param("id")})
}

// 添加用户
func AddUser(context *gin.Context) {
	type User struct {
		Name string `form:"name"`
		Age int `form:"age"`
	}
	var user User
	if err := context.ShouldBind(&user); err != nil {
		log.Fatal(err)
	}

	fmt.Printf("name: %v, age:%v\n", user.Name, user.Age)
	context.JSON(http.StatusOK, gin.H{
		"code": 0,
		"msg": "ok",
	})
}

// 删除用户
func DeleteUser(context *gin.Context) {
	context.JSON(http.StatusOK, gin.H{"id": context.Param("id")})
}

中间件

全局使用中间件

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
)

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

	// 全局使用该中间件
	engine.Use(MiddlewareDemo())

	engine.GET("/hello", func(context *gin.Context) {
		context.String(http.StatusOK, "hello")
	})

	engine.GET("/test", func(context *gin.Context) {
		context.String(http.StatusOK, "test")
	})

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err)
	}
}

// 自定义中间件
func MiddlewareDemo() gin.HandlerFunc {
	return func(context *gin.Context) {
		fmt.Println(context.Request.URL)
		fmt.Println(context.Request.RequestURI)
		fmt.Println(context.FullPath())
		fmt.Println(context.Request.Host)
		fmt.Println(context.Request.UserAgent())
	}
}

某一个视图函数使用中间件

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
)

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

	// 局部使用中间件
	engine.GET("/hello",MiddlewareDemo(), func(context *gin.Context) {
		context.String(http.StatusOK, "hello")
	})

	engine.GET("/test", func(context *gin.Context) {
		context.String(http.StatusOK, "test")
	})

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err)
	}
}

// 自定义中间件
func MiddlewareDemo() gin.HandlerFunc {
	return func(context *gin.Context) {
		fmt.Println(context.Request.URL)
		fmt.Println(context.Request.RequestURI)
		fmt.Println(context.FullPath())
		fmt.Println(context.Request.Host)
		fmt.Println(context.Request.UserAgent())
	}
}

中间件next

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"log"
	"net/http"
)

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

	// 局部使用中间件
	engine.GET("/hello",MiddlewareDemo(), func(context *gin.Context) {
		fmt.Println("我在执行业务代码")
		context.String(http.StatusOK, "hello")
	})

	engine.GET("/test", func(context *gin.Context) {
		context.String(http.StatusOK, "test")
	})

	if err := engine.Run(":8090"); err != nil {
		log.Fatal(err)
	}
}

// 自定义中间件
func MiddlewareDemo() gin.HandlerFunc {
	return func(context *gin.Context) {
		fmt.Println(context.Request.URL)
		fmt.Println(context.Request.RequestURI)
		fmt.Println(context.FullPath())
		fmt.Println(context.Request.Host)
		fmt.Println(context.Request.UserAgent())

		// 执行到next的时候会去执行业务代码
		context.Next()

		fmt.Println("我是视图函数执行结束了后执行的")
	}
}