Question

I’ve an issue with the post of an UIImage on a PHP server, when I post it, the image received is empty.

The method I use is :

- (void)uploadImage {
/*
 turning the image into a NSData object
 getting the image back out of the UIImageView
 setting the quality to 90
 */
NSData *imageData = UIImageJPEGRepresentation(myImage, 0.9);
// setting up the URL to post to
NSString *urlString = @"http://myserver/test.php";

// setting up the request object now
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:urlString]];
[request setHTTPMethod:@"POST"];

/*
 add some header info now
 we always need a boundary when we post a file
 also we need to set the content type

 You might want to generate a random boundary.. this is just the same
 as my output from wireshark on a valid html post
 */
NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];
NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
[request addValue:contentType forHTTPHeaderField: @"Content-Type"];

/*
 now lets create the body of the post
 */
NSMutableData *body = [NSMutableData data];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithString:@"Content-Disposition: form-data; name=\"userfile\"; filename=\"ipodfile.jpg\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[NSData dataWithData:imageData]];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
// setting the body of the post to the reqeust
[request setHTTPBody:body];

// now lets make the connection to the web
NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];

NSLog(returnString);
}

Taken from : http://iphone.zcentric.com/2008/08/29/post-a-uiimage-to-the-web/

Thanks for your help !

Answer 1

I suggest the use of ASIHTTPRequest for this kind of requests. You can do this much more easily with it. Here is an example to how send an image using ASIHTTPRequest:

// Initilize Queue
networkQueue = [[ASINetworkQueue alloc] init];
[networkQueue setUploadProgressDelegate:statusProgressView];
[networkQueue setRequestDidFinishSelector:@selector(imageRequestDidFinish:)];
[networkQueue setQueueDidFinishSelector:@selector(imageQueueDidFinish:)];
[networkQueue setRequestDidFailSelector:@selector(requestDidFail:)];
[networkQueue setShowAccurateProgress:true];
[networkQueue setDelegate:self];

NSData *imageData = UIImageJPEGRepresentation(yourImage, compression);

url = [NSURL URLWithString:@"http://myserver/upload.php"];
ASIFormDataRequest *request = [[[ASIFormDataRequest alloc] initWithURL:url] autorelease];
[request setPostValue:@"myImageName" forKey:@"name"]; 
[request addData:imageData withFileName:@"someFileName.jpeg" andContentType:@"image/jpeg" forKey:@"uploadedImage"];

[networkQueue addOperation:request];
[networkQueue go];

Hope it helps