go 通过http发送图片file内容

package main

import (
    
    "encoding/json"
    "fmt"
    
    "io/ioutil"
    "net/http"
    "net/url"
    "os"

    "bufio"
    "io"
    "mime/multipart"
    "net/smtp"
)

type addfeature struct {
    subid int    `json:"subid"`
    file  []byte `json:"file"`
}

func AddTemplateWeb(addr string) {
    // 创建表单文件
    // CreateFormFile 用来创建表单，第一个参数是字段名，第二个参数是文件名
    var feat addfeature
    buf := new(bytes.Buffer)
    writer := multipart.NewWriter(buf)
    writer.WriteField("sublib", "1")
    formFile, err := writer.CreateFormFile("file", "5.jpg")
    if err != nil {
        fmt.Println("Create form file failed: %s
", err)
    }

    // 从文件读取数据，写入表单
    srcFile, err := os.Open("/home/wei/1.jpg")
    if err != nil {
        fmt.Println("%Open source file failed: s
", err)
    }
    defer srcFile.Close()
    _, err = io.Copy(formFile, srcFile)
    if err != nil {
        fmt.Println("Write to form file falied: %s
", err)
    }

    // 发送表单
    contentType := writer.FormDataContentType()
    writer.Close() // 发送之前必须调用Close()以写入结尾行

    re, err := http.Post(addr, contentType, buf)
    fmt.Println(re)
    return
    
}