Gin上传文件

Posted 2021-11-23 Harris-H

tags:

篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了Gin上传文件相关的知识，希望对你有一定的参考价值。

文章目录

Gin上传文件

Gin上传文件

1.单文件上传

项目结构

main.go

package main

import (
	"fmt"
	"net/http"
	"path/filepath"

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

func main() {
	router := gin.Default()
	// Set a lower memory limit for multipart forms (default is 32 MiB)
	router.MaxMultipartMemory = 8 << 20               // 8 MiB
	router.Static("/", "./upload-file/single/public") //访问静态文件
	router.POST("/upload", func(c *gin.Context) { 
		name := c.PostForm("name")
		email := c.PostForm("email")

		// Source
		file, err := c.FormFile("file")
		if err != nil {
			c.String(http.StatusBadRequest, fmt.Sprintf("get form err: %s", err.Error()))
			return
		}

		filename := filepath.Base(file.Filename) //返回路径的最后一个元素
		pre := "./upload-file/single/images/"
		if err := c.SaveUploadedFile(file, pre+filename); err != nil {
			c.String(http.StatusBadRequest, fmt.Sprintf("upload file err: %s", err.Error()))
			return
		}

		c.String(http.StatusOK, fmt.Sprintf("File %s uploaded successfully with fields name=%s and email=%s.", file.Filename, name, email))
	})
	router.Run(":8080")
}

index.html

<!doctype html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <title>Single file upload</title>
</head>
<body>
<h1>Upload single file with fields</h1>

<form action="/upload" method="post" enctype="multipart/form-data">
    Name: <input type="text" name="name"><br>
    Email: <input type="email" name="email"><br>
    Files: <input type="file" name="file"><br><br>
    <input type="submit" value="Submit">
</form>
</body>

说明

a.Engine的MaxMultipartMemory

	// Value of 'maxMemory' param that is given to http.Request's ParseMultipartForm
	// method call.
	MaxMultipartMemory int64


	// Set a lower memory limit for multipart forms (default is 32 MiB)
	router.MaxMultipartMemory = 8 << 20 // 8 MiB

类型是int64， 8<<20 就是 $8B\\times 2^{20}=8MB$

b.filepath.Base(path)

返回路径的最后一个元素。

c. PostForm(key)

返回post提交的form表单对应键的值。

d. FormFile(name)

返回form表达对应名称的文件。

结果

2.多文件上传

main.go

package main

import (
	"fmt"
	"net/http"
	"path/filepath"

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

func main() {
	router := gin.Default()
	// Set a lower memory limit for multipart forms (default is 32 MiB)
	router.MaxMultipartMemory = 8 << 20 // 8 MiB
	router.Static("/", "./upload-file/multiple/public")
	router.POST("/upload", func(c *gin.Context) {
		name := c.PostForm("name")
		email := c.PostForm("email")

		// Multipart form
		form, err := c.MultipartForm()
		if err != nil {
			c.String(http.StatusBadRequest, fmt.Sprintf("get form err: %s", err.Error()))
			return
		}
		files := form.File["files"] //找到对应的name的input
		pre := "./upload-file/multiple/images/"
		for _, file := range files {	//遍历文件
			filename := filepath.Base(file.Filename)
			if err := c.SaveUploadedFile(file, pre+filename); err != nil {
				c.String(http.StatusBadRequest, fmt.Sprintf("upload file err: %s", err.Error()))
				return
			}
		}

		c.String(http.StatusOK, fmt.Sprintf("Uploaded successfully %d files with fields name=%s and email=%s.", len(files), name, email))
	})
	router.Run(":8081")
}

结果

说明

index.html 唯一的区别就是在input 里面加上multiple，这样就支持多文件了。

MultipartForm()方法返回一个form结构体。

type Form struct {
	Value map[string][]string
	File  map[string][]*FileHeader
}

包含两个属性，一个存放文件，一个存放value。

以上是关于Gin上传文件的主要内容，如果未能解决你的问题，请参考以下文章