我想在golang中渲染base64中的图像(这里是推特图标)
package main
import (
base64 "encoding/base64"
"fmt"
"io"
"net/http"
"strconv"
)
func pix(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "Hi there, I love %s!", r.URL.Path[1:])
var cookie *http.Cookie
cookie, err := r.Cookie("csrftoken")
if err != nil {
fmt.Printf("error")
fmt.Println(err)
}
fmt.Printf(cookie.Value)
w.Header().Set("Content-Type", "image/jpeg")
p, err := base64.StdEncoding.DecodeString("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")
if err != nil {
http.Error(w, "internal error", 500)
return
}
w.Header().Set("Content-Length", strconv.Itoa(len(p))) //len(dec)
io.WriteString(w, string(p))
}
func main() {
http.HandleFunc("/pix/", pix)
err := http.ListenAndServe(":9080", nil)
if err != nil {
fmt.Println(err)
}
}
但它没有显示任何内容,当我尝试转到URL时;它会下载包含错误的文件。任何人都知道为什么会这样?
答案 0 :(得分:6)
您正在向客户端写入数据而非图像。具体来说,这一行:
fmt.Fprintf(w, "Hi there, I love %s!", r.URL.Path[1:])
您的浏览器尝试将内容呈现为JPEG,但由于此额外数据而失败,因此它会提示您下载它。删除它,图片将正确显示。
您还应该关注@Mellow Marmot的建议,并使用w.Write(p)
代替io.WriteString(w, string(p))
。