Question

I am using NSURLConnection to send same data (NSString) to the server and i would like to add with them an image or a file so what’s the value of the content type?

Encoding

- (NSData *)encodingData:(NSMutableDictionary *)dictionary
{
    NSMutableArray *arrayPosts = [[NSMutableArray alloc] init];
    [dictionary enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
         NSString *encodedKey = [key stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
         NSString *encodedValue = [obj stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
        [arrayPosts addObject:[NSString stringWithFormat:@"%@=%@",encodedKey,encodedValue]];
    }];
    NSString *encodedArrayPosts = [arrayPosts componentsJoinedByString:@"&"];
    return [encodedArrayPosts dataUsingEncoding:NSUTF8StringEncoding];
}

Send Data

- (void)startAsyncRequest
{
   // Enable the network activity indicator in the status bar
   [self enableActivityIndicatorInStatusBar];

   // Setting of the request
   NSMutableURLRequest *urlRequest = [[NSMutableURLRequest alloc] initWithURL:self.url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:20.0];
   [urlRequest setHTTPMethod:self.method];
   [urlRequest setHTTPBody:[self encodingData:self.dictionaryPosts]];

   // Send the request
   NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self];

   if (connection) {
      // Connection succeded 
     self.receiveData = [NSMutableData data];
   } else {
      // Connection Failed
      self.error = @"Connection Failed";
      // Inform the user that the connection failed
      [self.delegate requestFailed:self];
   }
}

Answer 1

You need to pass the data into as stream type in your server

public InsertImage(Stream stream)

Something like that then parse the stream type.

This is how to build your request using some boundaries

- (NSURLRequest *)buildRequest:(NSData *)paramData fileName:(NSString *)name {
    NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
    NSString *charset = (NSString *)CFStringConvertEncodingToIANACharSetName(CFStringConvertNSStringEncodingToEncoding(NSUTF8StringEncoding));
    [request setURL:self.url];
    [request setHTTPMethod:self.method];

    NSString *boundary = @"0xKhTmLbOuNdArY";
    NSString *endBoundary = [NSString stringWithFormat:@"\r\n--%@\r\n", boundary];

    NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; charset=%@; boundary=%@", charset, boundary];
    [request addValue:contentType forHTTPHeaderField: @"Content-Type"];

    NSMutableData *tempPostData = [NSMutableData data]; 
    [tempPostData appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];

    // Sample Key Value for data
    [tempPostData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n", @"Key_Param"] dataUsingEncoding:NSUTF8StringEncoding]];
    [tempPostData appendData:@"Value_Param"] dataUsingEncoding:NSUTF8StringEncoding]];
    [tempPostData appendData:[endBoundary dataUsingEncoding:NSUTF8StringEncoding]];

    // Sample file to send as data
    [tempPostData appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"userfile\"; filename=\"%@\"\r\n", name] dataUsingEncoding:NSUTF8StringEncoding]];
    [tempPostData appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
    [tempPostData appendData:paramData];
    [tempPostData appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    [request setHTTPBody:tempPostData];
    return request;
}

You should get the stream type data on your server side and parse it, you can get the value base on the Key you pass e.g. Key_Param, and the name(fileName)of the file you send.