您好我正在使用android。我想将多部分数据发送到asp.net web api。我有一个json数据和多个images.I使用以下方法将数据发布到api
public int uploadFile(Context context,ArrayList<String> sourceFileUri,String json,String url1) {
// Toast.makeText(this,"uploading...", Toast.LENGTH_SHORT).show();
StrictMode.ThreadPolicy policy = new
StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
Log.i("uploadimage", "" + sourceFileUri.get(0));
HttpURLConnection conn = null;
DataOutputStream dos = null;
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead, bytesAvailable, bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 1024 * 1024;
File sourceFile = new File(android.os.Environment.getExternalStorageDirectory() + "/TrackonPro", sourceFileUri.get(0));
if (!sourceFile.isFile()) {
Log.i("uploadFile", "Source File not exist :" + sourceFileUri);
return 0;
}
else
{
// Toast.makeText(this,"found Path : "+imagePath , Toast.LENGTH_LONG).show();
try {
// Toast.makeText(this,"try....", Toast.LENGTH_LONG).show();
// open a URL connection to the Servlet
FileInputStream fileInputStream = new FileInputStream(sourceFile);
URL url = new URL(url1);
// Open a HTTP connection to the URL
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true); // Allow Inputs
conn.setDoOutput(true); // Allow Outputs
conn.setUseCaches(false); // Don't use a Cached Copy
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("ENCTYPE", "multipart/form-data");
conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
// Toast.makeText(this,"url : "+ url, Toast.LENGTH_LONG).show();
dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
// JSON STRING
dos.writeBytes("Content-Disposition: form-data; name=\"sanu\"");
dos.writeBytes(lineEnd);
dos.writeBytes(json);
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + lineEnd);
Log.i("immmm11",""+dos);
// IMAGE
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename="+ sourceFileUri + "" + lineEnd);
dos.writeBytes(lineEnd);
Log.i("immmm22", "" + dos);
// create a buffer of maximum size
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
// read file and write it into form...
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
// Toast.makeText(this,": while", Toast.LENGTH_LONG).show();
dos.write(buffer, 0, bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
}
// send multipart form data necesssary after file data...
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
Log.i("immmm33", "" + dos);
// Responses from the server (code and message)
serverResponseCode = conn.getResponseCode();
String serverResponseMessage = conn.getResponseMessage();
Log.i("uploadFile", "HTTP Response is : "+ serverResponseMessage + ": " + serverResponseCode);
// Toast.makeText(getApplicationContext(), "HTTP Response is : "+ serverResponseMessage + ": " + serverResponseCode,
// Toast.LENGTH_SHORT).show();
if(serverResponseCode == 200){
// Toast.makeText(context, "File Upload Complete.",
// Toast.LENGTH_SHORT).show();
}
//close the streams //
fileInputStream.close();
dos.flush();
dos.close();
} catch (MalformedURLException ex) {
ex.printStackTrace();
// Toast.makeText(context, "MalformedURLException",
// Toast.LENGTH_SHORT).show();
Log.e("Upload file to server", "error: " + ex.getMessage(), ex);
} catch (Exception e) {
e.printStackTrace();
// Toast.makeText(context, " Exception : try again ! ",
// Toast.LENGTH_SHORT).show();
// Log.i("Upload file to server Exception", "Exception : " + e.getMessage());
}
return serverResponseCode;
} // End else block
}
通过使用这个我能够上传图像到服务器。但是在服务器端没有收到文本。但使用Fidler应用程序到Web API的http post请求上传图像和文本？这个发送数据有什么问题吗？请提前帮助我
更新
现在我在服务器上收到了错误
System.IO.IOException: Error writing MIME multipart body part to output stream. ---> System.InvalidOperationException: The stream provider of type 'MultipartFormDataStreamProvider' threw an exception. ---> System.InvalidOperationException: Did not find required 'Content-Disposition' header field in MIME multipart body part.
at System.Net.Http.MultipartFormDataStreamProviderHelper.IsFileContent(HttpContent parent, HttpContentHeaders headers)
at System.Net.Http.MultipartFormDataStreamProvider.GetStream(HttpContent parent, HttpContentHeaders headers)
at System.Net.Http.MimeBodyPart.GetOutputStream()
--- End of inner exception stack trace ---
at System.Net.Http.MimeBodyPart.GetOutputStream()
at System.Net.Http.MimeBodyPart.<WriteSegment>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Net.Http.HttpContentMultipartExtensions.<MultipartReadAsync>d__8.MoveNext()
--- End of inner exception stack trace ---
at System.Net.Http.HttpContentMultipartExtensions.<MultipartReadAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Net.Http.HttpContentMultipartExtensions.<ReadAsMultipartAsync>d__0`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
at WebApplication.Areas.Json.Controllers.TravelClaimsController.<PostFormData>d__2.MoveNext()
答案 0 :(得分：0)
我已经使用此方法上传多部分请求（二进制数据和文本）
public class HttpClient {
...
方法是：
public void connectForMultipart() throws Exception {
con = (HttpURLConnection) ( new URL(url)).openConnection();
con.setRequestMethod("POST");
con.setDoInput(true);
con.setDoOutput(true);
con.setRequestProperty("Connection", "Keep-Alive");
con.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
con.connect();
os = con.getOutputStream();
}
和
public void addFormPart(String paramName, String value) throws Exception {
writeParamData(paramName, value);
}
private void writeParamData(String paramName, String value) throws Exception {
os.write( (delimiter + boundary + "\r\n").getBytes());
os.write( "Content-Type: text/plain\r\n".getBytes());
os.write( ("Content-Disposition: form-data; name=\"" + paramName + "\"\r\n").getBytes());;
os.write( ("\r\n" + value + "\r\n").getBytes());
}
其中
private String delimiter = "--";
private String boundary = "SwA"+Long.toString(System.currentTimeMillis())+"SwA";
The binary data (the image or something like that)
public void addFilePart(String paramName, String fileName, byte[] data) throws Exception {
os.write( (delimiter + boundary + "\r\n").getBytes());
os.write( ("Content-Disposition: form-data; name=\"" + paramName + "\"; filename=\"" + fileName + "\"\r\n" ).getBytes());
os.write( ("Content-Type: application/octet-stream\r\n" ).getBytes());
os.write( ("Content-Transfer-Encoding: binary\r\n" ).getBytes());
os.write("\r\n".getBytes());
os.write(data);
os.write("\r\n".getBytes());
}
当您调用HttpClient时，您需要添加部分：
HttpClient client = new HttpClient(url);
client.connectForMultipart();
client.addFormPart("param1", param1);
client.addFormPart("param2", param2);
client.addFilePart("file", "logo.png", baos.toByteArray());
client.finishMultipart();
和
public void finishMultipart() throws Exception {
os.write( (delimiter + boundary + delimiter + "\r\n").getBytes());
}
希望它对你有所帮助。要了解更多信息，请查看我的blog post