使用 C# 和 WebRequest 上传图像？
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Uploading an image using C# and WebRequest?
提问by Sergio Tapia
Here is the working code in Python (using cURL):
这是 Python 中的工作代码（使用 cURL）：
#!/usr/bin/python
import pycurl
c = pycurl.Curl()
values = [
("key", "YOUR_API_KEY"),
("image", (c.FORM_FILE, "file.png"))]
# OR: ("image", "http://example.com/example.jpg"))]
# OR: ("image", "BASE64_ENCODED_STRING"))]
c.setopt(c.URL, "http://imgur.com/api/upload.xml")
c.setopt(c.HTTPPOST, values)
c.perform()
c.close()
Here's what I have in C#:
这是我在 C# 中的内容：
public void UploadImage()
{
//I think this line is doing something wrong.
//byte[] x = File.ReadAllBytes(@"C:\Users\Sergio\documents\visual studio 2010\Projects\WpfApplication1\WpfApplication1\Test\hotness2.jpg");
//If I do it like this, using a direct URL everything works fine.
string parameters = @"key=1b9189df79bf3f8dff2125c22834210903&image=http://static.reddit.com/reddit.com.header.png"; //Convert.ToBase64String(x);
WebRequest webRequest = WebRequest.Create(new Uri("http://imgur.com/api/upload"));
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.Method = "POST";
byte[] bytes = Encoding.ASCII.GetBytes(parameters);
Stream os = null;
try
{ // send the Post
webRequest.ContentLength = bytes.Length; //Count bytes to send
os = webRequest.GetRequestStream();
os.Write(bytes, 0, bytes.Length); //Send it
}
catch (WebException ex)
{
MessageBox.Show(ex.Message, "HttpPost: Request error");
}
finally
{
if (os != null)
{
os.Close();
}
}
try
{ // get the response
WebResponse webResponse = webRequest.GetResponse();
StreamReader sr = new StreamReader(webResponse.GetResponseStream());
MessageBox.Show(sr.ReadToEnd().Trim());
}
catch (WebException ex)
{
MessageBox.Show(ex.Message, "HttpPost: Response error");
}
}
Now, the things I noticed is that when I changed my API key in the parameters string to "239231" or whatever number, the response I got was: "Invalid API key." So I think something must be working right.
现在，我注意到当我将参数字符串中的 API 密钥更改为“239231”或任何数字时，得到的响应是：“无效的 API 密钥”。所以我认为某些事情一定是正确的。
I placed my correctAPI key and now I get a different response: "Invalid image format. Try uploading a JPEG image."
我放置了正确的API 密钥，现在得到不同的响应：“图像格式无效。尝试上传 JPEG 图像。”
The service I'm using accepts almost every image format, so I am 100% certain the error is in the way I'm sending the file. Can anyone shed some light?
我使用的服务几乎接受所有图像格式，因此我 100% 确定错误在于我发送文件的方式。任何人都可以透露一些信息吗？
EDIT!!!
编辑！！！
It turns out when I upload a JPG image I get that gray box thing. If I upload a big jpg image I don't get anything. For example: http://i.imgur.com/gFsUY.jpg
事实证明，当我上传 JPG 图像时，我得到了那个灰色框的东西。如果我上传一个大的 jpg 图片，我什么也得不到。例如：http: //i.imgur.com/gFsUY.jpg
When I upload PNG's, the image uploaded doesn't even show.
当我上传 PNG 时，上传的图像甚至不显示。
I'm certain the issue is the encoding. What can I do?
我确定问题是编码。我能做什么？
EDIT 2!!!
编辑2！！！
Now I'm 100% certain that the problem lies in the first line of the method. The File.ReadAllBytes() must be doing something wrong. If I upload a URL file, every works peachy: http://imgur.com/sVH61.png
现在我 100% 确定问题出在方法的第一行。File.ReadAllBytes() 一定是做错了什么。如果我上传一个 URL 文件，每个都可以正常工作：http: //imgur.com/sVH61.png
I wonder what encoding I should use. :S
我想知道我应该使用什么编码。:S
采纳答案by Rubens Farias
Try this:
尝试这个：
string file = @"C:\Users\Sergio\documents\visual studio 2010\Projects\WpfApplication1\WpfApplication1\Test\Avatar.png";
string parameters = @"key=1df918979bf3f8dff2125c22834210903&image=" +
Convert.ToBase64String(File.ReadAllBytes(file));
回答by Paul Alan Taylor
Try changing :-
尝试改变：-
"application/x-www-form-urlencoded"
to
到
"multipart/form-data"
回答by feroze
Try adding the content-type for the jpg into your multipart boundary.
尝试将 jpg 的内容类型添加到您的多部分边界中。
See this uRL for examples (at the end)
请参阅此 uRL 以获取示例（最后）
http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2
http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2
回答by VladV
You should correctly form a multipart POST request. See an example here: Upload files with HTTPWebrequest (multipart/form-data)
您应该正确地形成一个多部分 POST 请求。在此处查看示例：使用 HTTPWebrequest (multipart/form-data) 上传文件
回答by cgd
Shot in the dark, but maybe create an instance of Image, save the file to a Stream and use that to read the bytes into an array then upload it.
在黑暗中拍摄，但可能会创建一个 Image 实例，将文件保存到 Stream 并使用它将字节读入数组然后上传。
As in:
如：
Image i = System.Drawing.Image.FromFile("wut.jpg");
Stream stm = new Stream();
System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality;
System.Drawing.Imaging.EncoderParameters paramz = new System.Drawing.Imaging.EncoderParameters(1);
myEncoderParameter = new EncoderParameter(myEncoder, 100L);
paramz.Param[0] = myEncoderParameter;
i.Save(stm, System.Drawing.Imaging.ImageFormat.Jpeg, paramz);
/* I'm lazy: code for reading Stream into byte[] here */
回答by Rajesh Kumar
Read image posted by in API
读取 API 中发布的图片
public IHttpActionResult UpdatePhysicianImage(HttpRequestMessage request)
{
try
{
var form = HttpContext.Current.Request.Form;
var model = JsonConvert.DeserializeObject<UserPic>(form["json"].ToString());
bool istoken = _appdevice.GettokenID(model.DeviceId);
if (!istoken)
{
statuscode = 0;
message = ErrorMessage.TockenNotvalid;
goto invalidtoken;
}
HttpResponseMessage result = null;
var httpRequest = HttpContext.Current.Request;
if (httpRequest.Files.Count > 0)
{
var docfiles = new List<string>();
foreach (string file in httpRequest.Files)
{
var postedFile = httpRequest.Files[file];
// var filePath = uploadPath + postedFile.FileName;
// string fileUrl = Utility.AbsolutePath("~/Data/User/" + model.UserId.ToString());
string fileUrl = Utility.AbsolutePath("~/" + Utility.UserDataFolder(model.UserId, "Document"));
if (!Directory.Exists(fileUrl))
{
Directory.CreateDirectory(fileUrl);
Directory.CreateDirectory(fileUrl + "\" + "Document");
Directory.CreateDirectory(fileUrl + "\" + "License");
Directory.CreateDirectory(fileUrl + "\" + "Profile");
}
string imageUrl = postedFile.FileName;
string naviPath = Utility.ProfileImagePath(model.UserId, imageUrl);
var path = Utility.AbsolutePath("~/" + naviPath);
postedFile.SaveAs(path);
docfiles.Add(path);
if (model.RoleId == 2)
{
var doctorEntity = _doctorProfile.GetNameVideoChat(model.UserId);
doctorEntity.ProfileImagePath = naviPath;
_doctorProfile.UpdateDoctorUpdProfile(doctorEntity);
}
else
{
var patientEntity = _PatientProfile.GetPatientByUserProfileId(model.UserId);
patientEntity.TumbImagePath = naviPath;
_PatientProfile.UpdatePatient(patientEntity);
}
}
result = Request.CreateResponse(HttpStatusCode.Created, docfiles);
}
else
{
result = Request.CreateResponse(HttpStatusCode.BadRequest);
}
}
catch (Exception e)
{
statuscode = 0;
message = "Error" + e.Message;
}
invalidtoken:
return Json(modeldata.GetData(statuscode, message));
}
