如何使用web api发布和接收文件
本文关键字:文件 何使用 web api | 更新日期: 2023-09-27 18:26:08
我有一个Api-Post方法,我希望它能够接受任何文件类型,看起来像这样:
[HttpPost]
public async Task<IHttpActionResult> Post()
{
if (!Request.Content.IsMimeMultipartContent())
{
throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
}
var provider = new MultipartMemoryStreamProvider();
await Request.Content.ReadAsMultipartAsync(provider);
if (provider.Contents.Count != 1)
{
throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.BadRequest,
"You must include exactly one file per request."));
}
var file = provider.Contents[0];
var filename = file.Headers.ContentDisposition.FileName.Trim(''"');
var buffer = await file.ReadAsByteArrayAsync();
}
当我试图在fiddler中发布图像时,这是有效的。然而,我正在编写一个客户端库,我有一个看起来像这样的方法:
public string PostAttachment(byte[] data, Uri endpoint, string contentType)
{
var request = (HttpWebRequest)WebRequest.Create(endpoint);
request.Method = "POST";
request.ContentType = contentType;
request.ContentLength = data.Length;
var stream = request.GetRequestStream();
stream.Write(data, 0, data.Length);
stream.Close();
var response = (HttpWebResponse) request.GetResponse();
using (var reader = new StreamReader(response.GetResponseStream()))
{
return reader.ReadToEnd();
}
}
每当我试图用这个发布图片时,我都会收到一个UnportedMediaType错误。我想这是因为我的图像不是多部分内容?有没有一种简单的方法来提出正确类型的请求?
如果我必须更改我的web api post方法,有没有一种简单的方法可以做到这一点,而无需将文件写入服务器并保存在内存中?
System.Net.Http
命名空间中的MultipartFormDataContent
将允许您发布多部分表单数据。
private async Task<string> PostAttachment(byte[] data, Uri url, string contentType)
{
HttpContent content = new ByteArrayContent(data);
content.Headers.ContentType = new MediaTypeHeaderValue(contentType);
using (var form = new MultipartFormDataContent())
{
form.Add(content);
using(var client = new HttpClient())
{
var response = await client.PostAsync(url, form);
return await response.Content.ReadAsStringAsync();
}
}
}