drtiwd06558 2016-05-09 10:03 采纳率: 100%
浏览 483

缓冲区问题不能在http.NewRequest golang的参数中将<type>用作类型io.Reader

I was having an issue when I was passing string in http.NewRequest in golang body param.

The error I got was :

cannot use req.Body (type string) as type io.Reader in argument to http.NewRequest: string does not implement io.Reader (missing Read method)

Similarly there are other use cases where the Buffer is required as an input instead of a particular type or an array of it. eg, byte[] when input required is buffer.

What did the error mean and what are ways of solving it and understanding what golang is trying to enforce.

Edit: This was the line I was having an issue with and did not find any references.

http.NewRequest(req.Method, req.Url, req.Body)

http.NewRequest(req.Method, req.Url, strings.NewReader(req.Body)) solves the issue. I was planning to add the answer as well (as an FYI type of question)

  • 写回答

1条回答 默认 最新

  • douzhuiqiu4923 2016-05-09 10:11

    This error means that the http.NewRequest method take a io.Reader interface as its body argument:

    func NewRequest(method, urlStr string, body io.Reader) (*Request, error)

    It is done this way so you can pass a file, a connection to a server, the response from something else to the request easily.

    The "problem" is that a string doesn't implement the io.Reader interface, which is defined as follow:

    type Reader interface {
       Read(p []byte) (n int, err error)

    Its not a huge problem, you can use the strings.Reader type which is a wrapper around a string that implement the said interface.

    func NewReader(s string) *Reader

    Tip: There also is a bytes.Reader type for the times you have a []byte to pass as parameter.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?



  • ¥15 关于螺旋焊缝的图像处理
  • ¥15 qt 散点图自定义图形
  • ¥100 将USDZ文件转化为带颜色的OBJ文件
  • ¥15 对象代号: , 表单: 不存在!
  • ¥15 WebSocket的问题
  • ¥15 centos上启动kylin后网页报错404
  • ¥20 使用hackrf进行信号收发时接收到的信号幅度太小
  • ¥15 WebSocket的问题
  • ¥15 BDSBAS-B1C和B1C信号有什么不同
  • ¥15 在半圆平面内随机生成点坐标