是否有任何类,库或某些代码段可帮助我使用HTTPWebrequest上传文件?
编辑2:
我不想上传到WebDAV文件夹或类似的文件。我想模拟一个浏览器,就像您将头像上传到论坛或通过Web应用程序中的表单上传文件一样。上传到使用多部分/表单数据的表单。
编辑:
WebClient不能满足我的要求,因此我正在寻找HTTPWebrequest解决方案。
是否有任何类,库或某些代码段可帮助我使用HTTPWebrequest上传文件?
编辑2:
我不想上传到WebDAV文件夹或类似的文件。我想模拟一个浏览器,就像您将头像上传到论坛或通过Web应用程序中的表单上传文件一样。上传到使用多部分/表单数据的表单。
编辑:
WebClient不能满足我的要求,因此我正在寻找HTTPWebrequest解决方案。
Answers:
接受了上面的代码,并进行了修复,因为它引发了内部服务器错误500。\ r \ n位置和空格错误等存在一些问题。对内存流应用了重构,直接写入请求流。结果如下:
public static void HttpUploadFile(string url, string file, string paramName, string contentType, NameValueCollection nvc) {
log.Debug(string.Format("Uploading {0} to {1}", file, url));
string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
wr.ContentType = "multipart/form-data; boundary=" + boundary;
wr.Method = "POST";
wr.KeepAlive = true;
wr.Credentials = System.Net.CredentialCache.DefaultCredentials;
Stream rs = wr.GetRequestStream();
string formdataTemplate = "Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}";
foreach (string key in nvc.Keys)
{
rs.Write(boundarybytes, 0, boundarybytes.Length);
string formitem = string.Format(formdataTemplate, key, nvc[key]);
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
rs.Write(formitembytes, 0, formitembytes.Length);
}
rs.Write(boundarybytes, 0, boundarybytes.Length);
string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";
string header = string.Format(headerTemplate, paramName, file, contentType);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
rs.Write(headerbytes, 0, headerbytes.Length);
FileStream fileStream = new FileStream(file, FileMode.Open, FileAccess.Read);
byte[] buffer = new byte[4096];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0) {
rs.Write(buffer, 0, bytesRead);
}
fileStream.Close();
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
rs.Write(trailer, 0, trailer.Length);
rs.Close();
WebResponse wresp = null;
try {
wresp = wr.GetResponse();
Stream stream2 = wresp.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
log.Debug(string.Format("File uploaded, server response is: {0}", reader2.ReadToEnd()));
} catch(Exception ex) {
log.Error("Error uploading file", ex);
if(wresp != null) {
wresp.Close();
wresp = null;
}
} finally {
wr = null;
}
}
和样本用法:
NameValueCollection nvc = new NameValueCollection();
nvc.Add("id", "TTR");
nvc.Add("btn-submit-photo", "Upload");
HttpUploadFile("http://your.server.com/upload",
@"C:\test\test.jpg", "file", "image/jpeg", nvc);
它可以扩展为处理多个文件,或者为每个文件多次调用。但是,它适合您的需求。
"\r\n--" + boundary + "--\r\n"
否则,其他文件将被切断。
我正在寻找类似的东西,位于:http : //bytes.com/groups/net-c/268661-how-upload-file-via-c-code(为了正确性而修改):
public static string UploadFilesToRemoteUrl(string url, string[] files, NameValueCollection formFields = null)
{
string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");
HttpWebRequest request = (HttpWebRequest) WebRequest.Create(url);
request.ContentType = "multipart/form-data; boundary=" +
boundary;
request.Method = "POST";
request.KeepAlive = true;
Stream memStream = new System.IO.MemoryStream();
var boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" +
boundary + "\r\n");
var endBoundaryBytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" +
boundary + "--");
string formdataTemplate = "\r\n--" + boundary +
"\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}";
if (formFields != null)
{
foreach (string key in formFields.Keys)
{
string formitem = string.Format(formdataTemplate, key, formFields[key]);
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
memStream.Write(formitembytes, 0, formitembytes.Length);
}
}
string headerTemplate =
"Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n" +
"Content-Type: application/octet-stream\r\n\r\n";
for (int i = 0; i < files.Length; i++)
{
memStream.Write(boundarybytes, 0, boundarybytes.Length);
var header = string.Format(headerTemplate, "uplTheFile", files[i]);
var headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
memStream.Write(headerbytes, 0, headerbytes.Length);
using (var fileStream = new FileStream(files[i], FileMode.Open, FileAccess.Read))
{
var buffer = new byte[1024];
var bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
memStream.Write(buffer, 0, bytesRead);
}
}
}
memStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);
request.ContentLength = memStream.Length;
using (Stream requestStream = request.GetRequestStream())
{
memStream.Position = 0;
byte[] tempBuffer = new byte[memStream.Length];
memStream.Read(tempBuffer, 0, tempBuffer.Length);
memStream.Close();
requestStream.Write(tempBuffer, 0, tempBuffer.Length);
}
using (var response = request.GetResponse())
{
Stream stream2 = response.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
return reader2.ReadToEnd();
}
}
更新:使用.NET 4.5(或通过从NuGet 添加Microsoft.Net.Http包的.NET 4.0 ),无需外部代码,扩展名和“低级” HTTP操作就可以实现此目的。这是一个例子:
// Perform the equivalent of posting a form with a filename and two files, in HTML:
// <form action="{url}" method="post" enctype="multipart/form-data">
// <input type="text" name="filename" />
// <input type="file" name="file1" />
// <input type="file" name="file2" />
// </form>
private async Task<System.IO.Stream> UploadAsync(string url, string filename, Stream fileStream, byte [] fileBytes)
{
// Convert each of the three inputs into HttpContent objects
HttpContent stringContent = new StringContent(filename);
// examples of converting both Stream and byte [] to HttpContent objects
// representing input type file
HttpContent fileStreamContent = new StreamContent(fileStream);
HttpContent bytesContent = new ByteArrayContent(fileBytes);
// Submit the form using HttpClient and
// create form data as Multipart (enctype="multipart/form-data")
using (var client = new HttpClient())
using (var formData = new MultipartFormDataContent())
{
// Add the HttpContent objects to the form data
// <input type="text" name="filename" />
formData.Add(stringContent, "filename", "filename");
// <input type="file" name="file1" />
formData.Add(fileStreamContent, "file1", "file1");
// <input type="file" name="file2" />
formData.Add(bytesContent, "file2", "file2");
// Invoke the request to the server
// equivalent to pressing the submit button on
// a form with attributes (action="{url}" method="post")
var response = await client.PostAsync(url, formData);
// ensure the request was a success
if (!response.IsSuccessStatusCode)
{
return null;
}
return await response.Content.ReadAsStreamAsync();
}
}
我的ASP.NET上载常见问题解答上有一篇文章,其中包含示例代码:使用RFC 1867 POST请求和HttpWebRequest / WebClient上载文件。此代码不会将文件加载到内存中(与上面的代码相反),支持多个文件,并支持表单值,设置凭据和Cookie等。
编辑:看起来像Axosoft删除了页面。谢谢你们。
仍然可以通过archive.org访问。
根据上面提供的代码,我添加了对多个文件的支持,还直接上传了流,而无需本地文件。
要将文件上传到包含某些发布参数的特定URL,请执行以下操作:
RequestHelper.PostMultipart(
"http://www.myserver.com/upload.php",
new Dictionary<string, object>() {
{ "testparam", "my value" },
{ "file", new FormFile() { Name = "image.jpg", ContentType = "image/jpeg", FilePath = "c:\\temp\\myniceimage.jpg" } },
{ "other_file", new FormFile() { Name = "image2.jpg", ContentType = "image/jpeg", Stream = imageDataStream } },
});
为了增强这一点,甚至可以从给定文件本身确定名称和mime类型。
public class FormFile
{
public string Name { get; set; }
public string ContentType { get; set; }
public string FilePath { get; set; }
public Stream Stream { get; set; }
}
public class RequestHelper
{
public static string PostMultipart(string url, Dictionary<string, object> parameters) {
string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
byte[] boundaryBytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.ContentType = "multipart/form-data; boundary=" + boundary;
request.Method = "POST";
request.KeepAlive = true;
request.Credentials = System.Net.CredentialCache.DefaultCredentials;
if(parameters != null && parameters.Count > 0) {
using(Stream requestStream = request.GetRequestStream()) {
foreach(KeyValuePair<string, object> pair in parameters) {
requestStream.Write(boundaryBytes, 0, boundaryBytes.Length);
if(pair.Value is FormFile) {
FormFile file = pair.Value as FormFile;
string header = "Content-Disposition: form-data; name=\"" + pair.Key + "\"; filename=\"" + file.Name + "\"\r\nContent-Type: " + file.ContentType + "\r\n\r\n";
byte[] bytes = System.Text.Encoding.UTF8.GetBytes(header);
requestStream.Write(bytes, 0, bytes.Length);
byte[] buffer = new byte[32768];
int bytesRead;
if(file.Stream == null) {
// upload from file
using(FileStream fileStream = File.OpenRead(file.FilePath)) {
while((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
requestStream.Write(buffer, 0, bytesRead);
fileStream.Close();
}
}
else {
// upload from given stream
while((bytesRead = file.Stream.Read(buffer, 0, buffer.Length)) != 0)
requestStream.Write(buffer, 0, bytesRead);
}
}
else {
string data = "Content-Disposition: form-data; name=\"" + pair.Key + "\"\r\n\r\n" + pair.Value;
byte[] bytes = System.Text.Encoding.UTF8.GetBytes(data);
requestStream.Write(bytes, 0, bytes.Length);
}
}
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
requestStream.Write(trailer, 0, trailer.Length);
requestStream.Close();
}
}
using(WebResponse response = request.GetResponse()) {
using(Stream responseStream = response.GetResponseStream())
using(StreamReader reader = new StreamReader(responseStream))
return reader.ReadToEnd();
}
}
}
像这样的东西很接近:(未经测试的代码)
byte[] data; // data goes here.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.Credentials = userNetworkCredentials;
request.Method = "PUT";
request.ContentType = "application/octet-stream";
request.ContentLength = data.Length;
Stream stream = request.GetRequestStream();
stream.Write(data,0,data.Length);
stream.Close();
response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream());
temp = reader.ReadToEnd();
reader.Close();
我认为您正在寻找更像WebClient的产品。
具体来说,就是UploadFile()。
进行了上述修改,它接受了一些头值和多个文件
NameValueCollection headers = new NameValueCollection();
headers.Add("Cookie", "name=value;");
headers.Add("Referer", "http://google.com");
NameValueCollection nvc = new NameValueCollection();
nvc.Add("name", "value");
HttpUploadFile(url, new string[] { "c:\\file1.txt", "c:\\file2.jpg" }, new string[] { "file", "image" }, new string[] { "application/octet-stream", "image/jpeg" }, nvc, headers);
public static void HttpUploadFile(string url, string[] file, string[] paramName, string[] contentType, NameValueCollection nvc, NameValueCollection headerItems)
{
//log.Debug(string.Format("Uploading {0} to {1}", file, url));
string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
foreach (string key in headerItems.Keys)
{
if (key == "Referer")
{
wr.Referer = headerItems[key];
}
else
{
wr.Headers.Add(key, headerItems[key]);
}
}
wr.ContentType = "multipart/form-data; boundary=" + boundary;
wr.Method = "POST";
wr.KeepAlive = true;
wr.Credentials = System.Net.CredentialCache.DefaultCredentials;
Stream rs = wr.GetRequestStream();
string formdataTemplate = "Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}";
foreach (string key in nvc.Keys)
{
rs.Write(boundarybytes, 0, boundarybytes.Length);
string formitem = string.Format(formdataTemplate, key, nvc[key]);
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
rs.Write(formitembytes, 0, formitembytes.Length);
}
rs.Write(boundarybytes, 0, boundarybytes.Length);
string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";
string header = "";
for(int i =0; i<file.Count();i++)
{
header = string.Format(headerTemplate, paramName[i], System.IO.Path.GetFileName(file[i]), contentType[i]);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
rs.Write(headerbytes, 0, headerbytes.Length);
FileStream fileStream = new FileStream(file[i], FileMode.Open, FileAccess.Read);
byte[] buffer = new byte[4096];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
rs.Write(buffer, 0, bytesRead);
}
fileStream.Close();
rs.Write(boundarybytes, 0, boundarybytes.Length);
}
rs.Close();
WebResponse wresp = null;
try
{
wresp = wr.GetResponse();
Stream stream2 = wresp.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
//log.Debug(string.Format("File uploaded, server response is: {0}", reader2.ReadToEnd()));
}
catch (Exception ex)
{
//log.Error("Error uploading file", ex);
wresp.Close();
wresp = null;
}
finally
{
wr = null;
}
}
\r\n--" + boundary + "--\r\n
VB示例(从另一篇文章的C#示例转换而成):
Private Sub HttpUploadFile( _
ByVal uri As String, _
ByVal filePath As String, _
ByVal fileParameterName As String, _
ByVal contentType As String, _
ByVal otherParameters As Specialized.NameValueCollection)
Dim boundary As String = "---------------------------" & DateTime.Now.Ticks.ToString("x")
Dim newLine As String = System.Environment.NewLine
Dim boundaryBytes As Byte() = Text.Encoding.ASCII.GetBytes(newLine & "--" & boundary & newLine)
Dim request As Net.HttpWebRequest = Net.WebRequest.Create(uri)
request.ContentType = "multipart/form-data; boundary=" & boundary
request.Method = "POST"
request.KeepAlive = True
request.Credentials = Net.CredentialCache.DefaultCredentials
Using requestStream As IO.Stream = request.GetRequestStream()
Dim formDataTemplate As String = "Content-Disposition: form-data; name=""{0}""{1}{1}{2}"
For Each key As String In otherParameters.Keys
requestStream.Write(boundaryBytes, 0, boundaryBytes.Length)
Dim formItem As String = String.Format(formDataTemplate, key, newLine, otherParameters(key))
Dim formItemBytes As Byte() = Text.Encoding.UTF8.GetBytes(formItem)
requestStream.Write(formItemBytes, 0, formItemBytes.Length)
Next key
requestStream.Write(boundaryBytes, 0, boundaryBytes.Length)
Dim headerTemplate As String = "Content-Disposition: form-data; name=""{0}""; filename=""{1}""{2}Content-Type: {3}{2}{2}"
Dim header As String = String.Format(headerTemplate, fileParameterName, filePath, newLine, contentType)
Dim headerBytes As Byte() = Text.Encoding.UTF8.GetBytes(header)
requestStream.Write(headerBytes, 0, headerBytes.Length)
Using fileStream As New IO.FileStream(filePath, IO.FileMode.Open, IO.FileAccess.Read)
Dim buffer(4096) As Byte
Dim bytesRead As Int32 = fileStream.Read(buffer, 0, buffer.Length)
Do While (bytesRead > 0)
requestStream.Write(buffer, 0, bytesRead)
bytesRead = fileStream.Read(buffer, 0, buffer.Length)
Loop
End Using
Dim trailer As Byte() = Text.Encoding.ASCII.GetBytes(newLine & "--" + boundary + "--" & newLine)
requestStream.Write(trailer, 0, trailer.Length)
End Using
Dim response As Net.WebResponse = Nothing
Try
response = request.GetResponse()
Using responseStream As IO.Stream = response.GetResponseStream()
Using responseReader As New IO.StreamReader(responseStream)
Dim responseText = responseReader.ReadToEnd()
Diagnostics.Debug.Write(responseText)
End Using
End Using
Catch exception As Net.WebException
response = exception.Response
If (response IsNot Nothing) Then
Using reader As New IO.StreamReader(response.GetResponseStream())
Dim responseText = reader.ReadToEnd()
Diagnostics.Debug.Write(responseText)
End Using
response.Close()
End If
Finally
request = Nothing
End Try
End Sub
我最近不得不处理这个问题-解决该问题的另一种方法是利用WebClient可继承的事实,并从那里更改基础WebRequest:
http://msdn.microsoft.com/zh-cn/library/system.net.webclient.getwebrequest(VS.80).aspx
我更喜欢C#,但是如果您坚持使用VB,结果将看起来像这样:
Public Class BigWebClient
Inherits WebClient
Protected Overrides Function GetWebRequest(ByVal address As System.Uri) As System.Net.WebRequest
Dim x As WebRequest = MyBase.GetWebRequest(address)
x.Timeout = 60 * 60 * 1000
Return x
End Function
End Class
'Use BigWebClient here instead of WebClient
我的评论还有另一个工作示例:
List<MimePart> mimeParts = new List<MimePart>();
try
{
foreach (string key in form.AllKeys)
{
StringMimePart part = new StringMimePart();
part.Headers["Content-Disposition"] = "form-data; name=\"" + key + "\"";
part.StringData = form[key];
mimeParts.Add(part);
}
int nameIndex = 0;
foreach (UploadFile file in files)
{
StreamMimePart part = new StreamMimePart();
if (string.IsNullOrEmpty(file.FieldName))
file.FieldName = "file" + nameIndex++;
part.Headers["Content-Disposition"] = "form-data; name=\"" + file.FieldName + "\"; filename=\"" + file.FileName + "\"";
part.Headers["Content-Type"] = file.ContentType;
part.SetStream(file.Data);
mimeParts.Add(part);
}
string boundary = "----------" + DateTime.Now.Ticks.ToString("x");
req.ContentType = "multipart/form-data; boundary=" + boundary;
req.Method = "POST";
long contentLength = 0;
byte[] _footer = Encoding.UTF8.GetBytes("--" + boundary + "--\r\n");
foreach (MimePart part in mimeParts)
{
contentLength += part.GenerateHeaderFooterData(boundary);
}
req.ContentLength = contentLength + _footer.Length;
byte[] buffer = new byte[8192];
byte[] afterFile = Encoding.UTF8.GetBytes("\r\n");
int read;
using (Stream s = req.GetRequestStream())
{
foreach (MimePart part in mimeParts)
{
s.Write(part.Header, 0, part.Header.Length);
while ((read = part.Data.Read(buffer, 0, buffer.Length)) > 0)
s.Write(buffer, 0, read);
part.Data.Dispose();
s.Write(afterFile, 0, afterFile.Length);
}
s.Write(_footer, 0, _footer.Length);
}
return (HttpWebResponse)req.GetResponse();
}
catch
{
foreach (MimePart part in mimeParts)
if (part.Data != null)
part.Data.Dispose();
throw;
}
还有使用示例:
UploadFile[] files = new UploadFile[]
{
new UploadFile(@"C:\2.jpg","new_file","image/jpeg") //new_file is id of upload field
};
NameValueCollection form = new NameValueCollection();
form["id_hidden_input"] = "value_hidden_inpu"; //there is additional param (hidden fields on page)
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(full URL of action);
// set credentials/cookies etc.
req.CookieContainer = hrm.CookieContainer; //hrm is my class. i copied all cookies from last request to current (for auth)
HttpWebResponse resp = HttpUploadHelper.Upload(req, files, form);
using (Stream s = resp.GetResponseStream())
using (StreamReader sr = new StreamReader(s))
{
string response = sr.ReadToEnd();
}
//profit!
我当时想进行文件上传,并在VB.NET中将一些参数添加到multipart / form-data请求中,而不是通过常规的表单发布。感谢@JoshCodes回答,我得到了我一直在寻找的方向。我正在发布我的解决方案,以帮助其他人找到一种执行带有文件和参数的发布的方法,而我尝试实现的html等效项是:html
<form action="your-api-endpoint" enctype="multipart/form-data" method="post">
<input type="hidden" name="action" value="api-method-name"/>
<input type="hidden" name="apiKey" value="gs1xxxxxxxxxxxxxex"/>
<input type="hidden" name="access" value="protected"/>
<input type="hidden" name="name" value="test"/>
<input type="hidden" name="title" value="test"/>
<input type="hidden" name="signature" value="cf1d4xxxxxxxxcd5"/>
<input type="file" name="file"/>
<input type="submit" name="_upload" value="Upload"/>
</form>
由于我必须提供apiKey和签名(这是请求参数和api键串联字符串的计算校验和),因此我需要在服务器端进行操作。我需要在服务器端执行此操作的另一个原因是,可以通过指向服务器上已经存在的文件(提供路径)随时执行文件发布操作,因此在表单创建过程中不会手动选择文件post因此表单数据文件将不包含文件流。否则我可以通过ajax回调计算校验和,然后使用jQuery通过html post提交文件。我正在使用.net 4.0版,并且在实际解决方案中无法升级到4.5。所以我不得不使用nuget cmd安装Microsoft.Net.Http
PM> install-package Microsoft.Net.Http
Private Function UploadFile(req As ApiRequest, filePath As String, fileName As String) As String
Dim result = String.empty
Try
''//Get file stream
Dim paramFileStream As Stream = File.OpenRead(filePath)
Dim fileStreamContent As HttpContent = New StreamContent(paramFileStream)
Using client = New HttpClient()
Using formData = New MultipartFormDataContent()
''// This adds parameter name ("action")
''// parameter value (req.Action) to form data
formData.Add(New StringContent(req.Action), "action")
formData.Add(New StringContent(req.ApiKey), "apiKey")
For Each param In req.Parameters
formData.Add(New StringContent(param.Value), param.Key)
Next
formData.Add(New StringContent(req.getRequestSignature.Qualifier), "signature")
''//This adds the file stream and file info to form data
formData.Add(fileStreamContent, "file", fileName)
''//We are now sending the request
Dim response = client.PostAsync(GetAPIEndpoint(), formData).Result
''//We are here reading the response
Dim readR = New StreamReader(response.Content.ReadAsStreamAsync().Result, Encoding.UTF8)
Dim respContent = readR.ReadToEnd()
If Not response.IsSuccessStatusCode Then
result = "Request Failed : Code = " & response.StatusCode & "Reason = " & response.ReasonPhrase & "Message = " & respContent
End If
result.Value = respContent
End Using
End Using
Catch ex As Exception
result = "An error occurred : " & ex.Message
End Try
Return result
End Function
修改后的@CristianRomanescu代码可用于内存流,将文件接受为字节数组,允许空nvc,返回请求响应以及使用Authorization-header。使用Web Api 2测试了代码。
private string HttpUploadFile(string url, byte[] file, string fileName, string paramName, string contentType, NameValueCollection nvc, string authorizationHeader)
{
string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
wr.ContentType = "multipart/form-data; boundary=" + boundary;
wr.Method = "POST";
wr.Headers.Add("Authorization", authorizationHeader);
wr.KeepAlive = true;
Stream rs = wr.GetRequestStream();
string formdataTemplate = "Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}";
if (nvc != null)
{
foreach (string key in nvc.Keys)
{
rs.Write(boundarybytes, 0, boundarybytes.Length);
string formitem = string.Format(formdataTemplate, key, nvc[key]);
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
rs.Write(formitembytes, 0, formitembytes.Length);
}
}
rs.Write(boundarybytes, 0, boundarybytes.Length);
string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";
string header = string.Format(headerTemplate, paramName, fileName, contentType);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
rs.Write(headerbytes, 0, headerbytes.Length);
rs.Write(file, 0, file.Length);
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
rs.Write(trailer, 0, trailer.Length);
rs.Close();
WebResponse wresp = null;
try
{
wresp = wr.GetResponse();
Stream stream2 = wresp.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
var response = reader2.ReadToEnd();
return response;
}
catch (Exception ex)
{
if (wresp != null)
{
wresp.Close();
wresp = null;
}
return null;
}
finally
{
wr = null;
}
}
测试代码:
[HttpPost]
[Route("postformdata")]
public IHttpActionResult PostFormData()
{
// Check if the request contains multipart/form-data.
if (!Request.Content.IsMimeMultipartContent())
{
throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
}
var provider = new MultipartMemoryStreamProvider();
try
{
// Read the form data.
var result = Request.Content.ReadAsMultipartAsync(provider).Result;
string response = "";
// This illustrates how to get the file names.
foreach (var file in provider.Contents)
{
var fileName = file.Headers.ContentDisposition.FileName.Trim('\"');
var buffer = file.ReadAsByteArrayAsync().Result;
response = HttpUploadFile("https://localhost/api/v1/createfromfile", buffer, fileName, "file", "application/pdf", null, "AuthorizationKey");
}
return Ok(response);
}
catch (System.Exception e)
{
return InternalServerError();
}
}
对我来说,以下作品(大部分是从以下所有答案中得到启发),我从埃拉德的答案开始,并进行了修改/简化,以适应我的需要(不删除文件形式的输入,仅删除一个文件,...)。
希望它可以帮助某人:)
(PS:我知道未实现异常处理,并且假定它是在类内部编写的,因此我可能需要进行一些集成工作...)
private void uploadFile()
{
Random rand = new Random();
string boundary = "----boundary" + rand.Next().ToString();
Stream data_stream;
byte[] header = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"file_path\"; filename=\"" + System.IO.Path.GetFileName(this.file) + "\"\r\nContent-Type: application/octet-stream\r\n\r\n");
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
// Do the request
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(MBF_URL);
request.UserAgent = "My Toolbox";
request.Method = "POST";
request.KeepAlive = true;
request.ContentType = "multipart/form-data; boundary=" + boundary;
data_stream = request.GetRequestStream();
data_stream.Write(header, 0, header.Length);
byte[] file_bytes = System.IO.File.ReadAllBytes(this.file);
data_stream.Write(file_bytes, 0, file_bytes.Length);
data_stream.Write(trailer, 0, trailer.Length);
data_stream.Close();
// Read the response
WebResponse response = request.GetResponse();
data_stream = response.GetResponseStream();
StreamReader reader = new StreamReader(data_stream);
this.url = reader.ReadToEnd();
if (this.url == "") { this.url = "No response :("; }
reader.Close();
data_stream.Close();
response.Close();
}
不知道这是否以前发布过,但是我已经使用WebClient进行了工作。我阅读了WebClient的文档。他们提出的关键点是
如果BaseAddress属性不是一个空字符串(“”),并且address不包含绝对URI,则address必须是与BaseAddress组合以形成所请求数据的绝对URI的相对URI。如果QueryString属性不是空字符串,则将其附加到address。
因此,我所做的就是wc.QueryString.Add(“ source”,generateImage)来添加不同的查询参数,并以某种方式将属性名称与我上传的图像进行匹配。希望能帮助到你
public void postImageToFacebook(string generatedImage, string fbGraphUrl)
{
WebClient wc = new WebClient();
byte[] bytes = System.IO.File.ReadAllBytes(generatedImage);
wc.QueryString.Add("source", generatedImage);
wc.QueryString.Add("message", "helloworld");
wc.UploadFile(fbGraphUrl, generatedImage);
wc.Dispose();
}
我写了一个使用WebClient的类,可以追溯到何时进行多部分表单上传。
http://ferozedaud.blogspot.com/2010/03/multipart-form-upload-helper.html
///
/// MimePart
/// Abstract class for all MimeParts
///
abstract class MimePart
{
public string Name { get; set; }
public abstract string ContentDisposition { get; }
public abstract string ContentType { get; }
public abstract void CopyTo(Stream stream);
public String Boundary
{
get;
set;
}
}
class NameValuePart : MimePart
{
private NameValueCollection nameValues;
public NameValuePart(NameValueCollection nameValues)
{
this.nameValues = nameValues;
}
public override void CopyTo(Stream stream)
{
string boundary = this.Boundary;
StringBuilder sb = new StringBuilder();
foreach (object element in this.nameValues.Keys)
{
sb.AppendFormat("--{0}", boundary);
sb.Append("\r\n");
sb.AppendFormat("Content-Disposition: form-data; name=\"{0}\";", element);
sb.Append("\r\n");
sb.Append("\r\n");
sb.Append(this.nameValues[element.ToString()]);
sb.Append("\r\n");
}
sb.AppendFormat("--{0}", boundary);
sb.Append("\r\n");
//Trace.WriteLine(sb.ToString());
byte [] data = Encoding.ASCII.GetBytes(sb.ToString());
stream.Write(data, 0, data.Length);
}
public override string ContentDisposition
{
get { return "form-data"; }
}
public override string ContentType
{
get { return String.Empty; }
}
}
class FilePart : MimePart
{
private Stream input;
private String contentType;
public FilePart(Stream input, String name, String contentType)
{
this.input = input;
this.contentType = contentType;
this.Name = name;
}
public override void CopyTo(Stream stream)
{
StringBuilder sb = new StringBuilder();
sb.AppendFormat("Content-Disposition: {0}", this.ContentDisposition);
if (this.Name != null)
sb.Append("; ").AppendFormat("name=\"{0}\"", this.Name);
if (this.FileName != null)
sb.Append("; ").AppendFormat("filename=\"{0}\"", this.FileName);
sb.Append("\r\n");
sb.AppendFormat(this.ContentType);
sb.Append("\r\n");
sb.Append("\r\n");
// serialize the header data.
byte[] buffer = Encoding.ASCII.GetBytes(sb.ToString());
stream.Write(buffer, 0, buffer.Length);
// send the stream.
byte[] readBuffer = new byte[1024];
int read = input.Read(readBuffer, 0, readBuffer.Length);
while (read > 0)
{
stream.Write(readBuffer, 0, read);
read = input.Read(readBuffer, 0, readBuffer.Length);
}
// write the terminating boundary
sb.Length = 0;
sb.Append("\r\n");
sb.AppendFormat("--{0}", this.Boundary);
sb.Append("\r\n");
buffer = Encoding.ASCII.GetBytes(sb.ToString());
stream.Write(buffer, 0, buffer.Length);
}
public override string ContentDisposition
{
get { return "file"; }
}
public override string ContentType
{
get {
return String.Format("content-type: {0}", this.contentType);
}
}
public String FileName { get; set; }
}
///
/// Helper class that encapsulates all file uploads
/// in a mime part.
///
class FilesCollection : MimePart
{
private List files;
public FilesCollection()
{
this.files = new List();
this.Boundary = MultipartHelper.GetBoundary();
}
public int Count
{
get { return this.files.Count; }
}
public override string ContentDisposition
{
get
{
return String.Format("form-data; name=\"{0}\"", this.Name);
}
}
public override string ContentType
{
get { return String.Format("multipart/mixed; boundary={0}", this.Boundary); }
}
public override void CopyTo(Stream stream)
{
// serialize the headers
StringBuilder sb = new StringBuilder(128);
sb.Append("Content-Disposition: ").Append(this.ContentDisposition).Append("\r\n");
sb.Append("Content-Type: ").Append(this.ContentType).Append("\r\n");
sb.Append("\r\n");
sb.AppendFormat("--{0}", this.Boundary).Append("\r\n");
byte[] headerBytes = Encoding.ASCII.GetBytes(sb.ToString());
stream.Write(headerBytes, 0, headerBytes.Length);
foreach (FilePart part in files)
{
part.Boundary = this.Boundary;
part.CopyTo(stream);
}
}
public void Add(FilePart part)
{
this.files.Add(part);
}
}
///
/// Helper class to aid in uploading multipart
/// entities to HTTP web endpoints.
///
class MultipartHelper
{
private static Random random = new Random(Environment.TickCount);
private List formData = new List();
private FilesCollection files = null;
private MemoryStream bufferStream = new MemoryStream();
private string boundary;
public String Boundary { get { return boundary; } }
public static String GetBoundary()
{
return Environment.TickCount.ToString("X");
}
public MultipartHelper()
{
this.boundary = MultipartHelper.GetBoundary();
}
public void Add(NameValuePart part)
{
this.formData.Add(part);
part.Boundary = boundary;
}
public void Add(FilePart part)
{
if (files == null)
{
files = new FilesCollection();
}
this.files.Add(part);
}
public void Upload(WebClient client, string address, string method)
{
// set header
client.Headers.Add(HttpRequestHeader.ContentType, "multipart/form-data; boundary=" + this.boundary);
Trace.WriteLine("Content-Type: multipart/form-data; boundary=" + this.boundary + "\r\n");
// first, serialize the form data
foreach (NameValuePart part in this.formData)
{
part.CopyTo(bufferStream);
}
// serialize the files.
this.files.CopyTo(bufferStream);
if (this.files.Count > 0)
{
// add the terminating boundary.
StringBuilder sb = new StringBuilder();
sb.AppendFormat("--{0}", this.Boundary).Append("\r\n");
byte [] buffer = Encoding.ASCII.GetBytes(sb.ToString());
bufferStream.Write(buffer, 0, buffer.Length);
}
bufferStream.Seek(0, SeekOrigin.Begin);
Trace.WriteLine(Encoding.ASCII.GetString(bufferStream.ToArray()));
byte [] response = client.UploadData(address, method, bufferStream.ToArray());
Trace.WriteLine("----- RESPONSE ------");
Trace.WriteLine(Encoding.ASCII.GetString(response));
}
///
/// Helper class that encapsulates all file uploads
/// in a mime part.
///
class FilesCollection : MimePart
{
private List files;
public FilesCollection()
{
this.files = new List();
this.Boundary = MultipartHelper.GetBoundary();
}
public int Count
{
get { return this.files.Count; }
}
public override string ContentDisposition
{
get
{
return String.Format("form-data; name=\"{0}\"", this.Name);
}
}
public override string ContentType
{
get { return String.Format("multipart/mixed; boundary={0}", this.Boundary); }
}
public override void CopyTo(Stream stream)
{
// serialize the headers
StringBuilder sb = new StringBuilder(128);
sb.Append("Content-Disposition: ").Append(this.ContentDisposition).Append("\r\n");
sb.Append("Content-Type: ").Append(this.ContentType).Append("\r\n");
sb.Append("\r\n");
sb.AppendFormat("--{0}", this.Boundary).Append("\r\n");
byte[] headerBytes = Encoding.ASCII.GetBytes(sb.ToString());
stream.Write(headerBytes, 0, headerBytes.Length);
foreach (FilePart part in files)
{
part.Boundary = this.Boundary;
part.CopyTo(stream);
}
}
public void Add(FilePart part)
{
this.files.Add(part);
}
}
}
class Program
{
static void Main(string[] args)
{
Trace.Listeners.Add(new ConsoleTraceListener());
try
{
using (StreamWriter sw = new StreamWriter("testfile.txt", false))
{
sw.Write("Hello there!");
}
using (Stream iniStream = File.OpenRead(@"c:\platform.ini"))
using (Stream fileStream = File.OpenRead("testfile.txt"))
using (WebClient client = new WebClient())
{
MultipartHelper helper = new MultipartHelper();
NameValueCollection props = new NameValueCollection();
props.Add("fname", "john");
props.Add("id", "acme");
helper.Add(new NameValuePart(props));
FilePart filepart = new FilePart(fileStream, "pics1", "text/plain");
filepart.FileName = "1.jpg";
helper.Add(filepart);
FilePart ini = new FilePart(iniStream, "pics2", "text/plain");
ini.FileName = "inifile.ini";
helper.Add(ini);
helper.Upload(client, "http://localhost/form.aspx", "POST");
}
}
catch (Exception e)
{
Trace.WriteLine(e);
}
}
}
这将适用于所有版本的.NET框架。
我永远无法使示例正常工作,将其发送到服务器时总是会收到500错误。
但是我在此网址中遇到了一种非常优雅的方法
它很容易扩展,显然可以与二进制文件以及XML一起使用。
您可以使用与此类似的名称
class Program
{
public static string gsaFeedURL = "http://yourGSA.domain.com:19900/xmlfeed";
static void Main()
{
try
{
postWebData();
}
catch (Exception ex)
{
}
}
// new one I made from C# web service
public static void postWebData()
{
StringDictionary dictionary = new StringDictionary();
UploadSpec uploadSpecs = new UploadSpec();
UTF8Encoding encoding = new UTF8Encoding();
byte[] bytes;
Uri gsaURI = new Uri(gsaFeedURL); // Create new URI to GSA feeder gate
string sourceURL = @"C:\FeedFile.xml"; // Location of the XML feed file
// Two parameters to send
string feedtype = "full";
string datasource = "test";
try
{
// Add the parameter values to the dictionary
dictionary.Add("feedtype", feedtype);
dictionary.Add("datasource", datasource);
// Load the feed file created and get its bytes
XmlDocument xml = new XmlDocument();
xml.Load(sourceURL);
bytes = Encoding.UTF8.GetBytes(xml.OuterXml);
// Add data to upload specs
uploadSpecs.Contents = bytes;
uploadSpecs.FileName = sourceURL;
uploadSpecs.FieldName = "data";
// Post the data
if ((int)HttpUpload.Upload(gsaURI, dictionary, uploadSpecs).StatusCode == 200)
{
Console.WriteLine("Successful.");
}
else
{
// GSA POST not successful
Console.WriteLine("Failure.");
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
签出MyToolkit库:
var request = new HttpPostRequest("http://www.server.com");
request.Data.Add("name", "value"); // POST data
request.Files.Add(new HttpPostFile("name", "file.jpg", "path/to/file.jpg"));
await Http.PostAsync(request, OnRequestFinished);
此方法适用于同时上传多张图片
var flagResult = new viewModel();
string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
wr.ContentType = "multipart/form-data; boundary=" + boundary;
wr.Method = method;
wr.KeepAlive = true;
wr.Credentials = System.Net.CredentialCache.DefaultCredentials;
Stream rs = wr.GetRequestStream();
string path = @filePath;
System.IO.DirectoryInfo folderInfo = new DirectoryInfo(path);
foreach (FileInfo file in folderInfo.GetFiles())
{
rs.Write(boundarybytes, 0, boundarybytes.Length);
string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";
string header = string.Format(headerTemplate, paramName, file, contentType);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
rs.Write(headerbytes, 0, headerbytes.Length);
FileStream fileStream = new FileStream(file.FullName, FileMode.Open, FileAccess.Read);
byte[] buffer = new byte[4096];
int bytesRead = 0;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
{
rs.Write(buffer, 0, bytesRead);
}
fileStream.Close();
}
byte[] trailer = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
rs.Write(trailer, 0, trailer.Length);
rs.Close();
WebResponse wresp = null;
try
{
wresp = wr.GetResponse();
Stream stream2 = wresp.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
var result = reader2.ReadToEnd();
var cList = JsonConvert.DeserializeObject<HttpViewModel>(result);
if (cList.message=="images uploaded!")
{
flagResult.success = true;
}
}
catch (Exception ex)
{
//log.Error("Error uploading file", ex);
if (wresp != null)
{
wresp.Close();
wresp = null;
}
}
finally
{
wr = null;
}
return flagResult;
}
我意识到这可能真的很晚,但是我正在寻找相同的解决方案。我从Microsoft代表处发现以下回应
private void UploadFilesToRemoteUrl(string url, string[] files, string logpath, NameValueCollection nvc)
{
long length = 0;
string boundary = "----------------------------" +
DateTime.Now.Ticks.ToString("x");
HttpWebRequest httpWebRequest2 = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest2.ContentType = "multipart/form-data; boundary=" +
boundary;
httpWebRequest2.Method = "POST";
httpWebRequest2.KeepAlive = true;
httpWebRequest2.Credentials = System.Net.CredentialCache.DefaultCredentials;
Stream memStream = new System.IO.MemoryStream();
byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
string formdataTemplate = "\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}";
foreach(string key in nvc.Keys)
{
string formitem = string.Format(formdataTemplate, key, nvc[key]);
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
memStream.Write(formitembytes, 0, formitembytes.Length);
}
memStream.Write(boundarybytes,0,boundarybytes.Length);
string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n Content-Type: application/octet-stream\r\n\r\n";
for(int i=0;i<files.Length;i++)
{
string header = string.Format(headerTemplate,"file"+i,files[i]);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
memStream.Write(headerbytes,0,headerbytes.Length);
FileStream fileStream = new FileStream(files[i], FileMode.Open,
FileAccess.Read);
byte[] buffer = new byte[1024];
int bytesRead = 0;
while ( (bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0 )
{
memStream.Write(buffer, 0, bytesRead);
}
memStream.Write(boundarybytes,0,boundarybytes.Length);
fileStream.Close();
}
httpWebRequest2.ContentLength = memStream.Length;
Stream requestStream = httpWebRequest2.GetRequestStream();
memStream.Position = 0;
byte[] tempBuffer = new byte[memStream.Length];
memStream.Read(tempBuffer,0,tempBuffer.Length);
memStream.Close();
requestStream.Write(tempBuffer,0,tempBuffer.Length );
requestStream.Close();
WebResponse webResponse2 = httpWebRequest2.GetResponse();
Stream stream2 = webResponse2.GetResponseStream();
StreamReader reader2 = new StreamReader(stream2);
webResponse2.Close();
httpWebRequest2 = null;
webResponse2 = null;
}