是否有任何类，库或一些代码片段，将帮助我上传文件与HTTPWebrequest?
编辑2:
我不想上传到WebDAV文件夹或类似的东西。我想模拟一个浏览器，就像你上传你的头像到一个论坛或通过一个web应用程序中的表单上传一个文件。上传到一个使用multipart/form-data的表单。
编辑:
WebClient不覆盖我的需求，所以我正在寻找一个解决方案与HTTPWebrequest。
当前回答
基于上面提供的代码，我添加了对多个文件的支持，也可以直接上传流，而不需要有本地文件。
要将文件上传到包含一些post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 } },
});
为了进一步增强这一点，可以从给定的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();
}
}
}
其他回答
基于上面提供的代码，我添加了对多个文件的支持，也可以直接上传流，而不需要有本地文件。
要将文件上传到包含一些post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 } },
});
为了进一步增强这一点，可以从给定的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();
}
}
}
类似这样的代码很接近:(未测试的代码)
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();
我永远不能让例子正常工作，我总是收到一个500错误时，把它发送到服务器。
然而，我在这个url中遇到了一个非常优雅的方法
它很容易扩展，显然可以处理二进制文件和XML。
你可以用类似的方法来称呼它
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);
}
}
}
我想在VB中做文件上传和添加一些参数到multipart/form-data请求。NET而不是通过正规的表单发布。 感谢@JoshCodes的回答，我找到了我一直在寻找的方向。 我发布我的解决方案是为了帮助其他人找到一种方法来使用文件和参数来执行帖子 html等价于我试图实现的是: 超文本标记语言
<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>
Due to the fact that I have to provide the apiKey and the signature (which is a calculated checksum of the request parameters and api key concatenated string), I needed to do it server side. The other reason I needed to do it server side is the fact that the post of the file can be performed at any time by pointing to a file already on the server (providing the path), so there would be no manually selected file during form post thus form data file would not contain the file stream.Otherwise I could have calculated the checksum via an ajax callback and submitted the file through the html post using JQuery. I am using .net version 4.0 and cannot upgrade to 4.5 in the actual solution. So I had to install the Microsoft.Net.Http using nuget cmd
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
客户端使用转换文件到ToBase64String，使用Xml发布后 到服务器调用，这个服务器使用File.WriteAllBytes(path,Convert.FromBase64String(dataFile_Client_sent))。
好幸运!
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