不说废话直接贴代码，代码有注释。
package main
import (
"fmt"
"io"
"io/ioutil"
"log"
"net/http"
"os"
"reflect"
)
const( UPLOAD_DIR="d:/uploads")
//这是上传图片的handler
func uploadHandler(w http.ResponseWriter, r *http.Request){
if r.Method =="GET"{
//将html写入到类型为http.ResponseWriter的w实例中
io.WriteString(w,"<html><form method=\"POST\" action=\"upload\" " +
"enctype=\"multipart/form-data\">"+
"Choose an image to upload:<input name =\"image\" type=\"file\" />"+
"<input type=\"submit\" value=\"Upload\" />"+
"</from></html>")
return
}
if r.Method =="POST"{
//r.FormFile用来获取接受的请求的文件句柄。
f,h,err :=r.FormFile("image")
if err !=nil{
http.Error(w,err.Error(),http.StatusInternalServerError)
return
}
filename :=h.Filename
fmt.Println(filename)
defer f.Close()
t,err := os.Create(UPLOAD_DIR +"/"+filename)
if err !=nil{
http.Error(w,err.Error(),http.StatusInternalServerError)
return
}
defer t.Close()
//将文件复制到指定目录的指定文件
if _,err :=io.Copy(t,f);err !=nil{
http.Error(w,err.Error(),http.StatusInternalServerError)
return
}
http.Redirect(w,r,"/view?id="+filename,http.StatusFound)
}
}
func viewHandler(w http.ResponseWriter,r *http.Request){
imageId :=r.FormValue("id")
imagePath:=UPLOAD_DIR +"/"+imageId
w.Header().Set("Content-Tpye","image")
//读取图片，并将图片写入到http.ResponseWriter
http.ServeFile(w,r,imagePath)
}
func listHandler(w http.ResponseWriter,r *http.Request){
//遍历指定目录，他读取目录并返回排好序的文件以及子目录名
FileInfoArr,err :=ioutil.ReadDir("d:/uploads")
if err !=nil{
http.Error(w,err.Error(),http.StatusInternalServerError)
return
}
var listHtml string
for _,fileInfo :=range FileInfoArr{
imgid :=fileInfo.Name
fmt.Println(reflect.TypeOf(imgid))
listHtml +="<li><a href=\"/view?id="+imgid()+"\">"+imgid()+"</a></li>"
}
io.WriteString(w,"<html>"+listHtml+"</html>")
}
func main(){
//服务注册
http.HandleFunc("/",listHandler)
http.HandleFunc("/upload",uploadHandler)
http.HandleFunc("/view",viewHandler)
//创建server服务
err :=http.ListenAndServe(":8080",nil)
if err != nil{
log.Fatal("ListenAndServer",err.Error())
}
}