I have the objective C code:
NSString * url = [NSString stringWithFormat:@"http://tragicclothing.co.uk/Retort/imageupload.php"];
NSMutableURLRequest *request=[NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];
[request setHTTPMethod:@"POST"];
NSString *boundary = @"---------------------------14737809831466499882746641449";
NSMutableData *body = [[NSMutableData alloc]init];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"image\"; filename=\"image.jpg\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[@"Content-Type: audio/basic\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:_imageDataToSend];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[request setHTTPBody:body];
NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
[request addValue:contentType forHTTPHeaderField: @"Content-Type"];
//Send the Request
NSData* returnData = [NSURLConnection sendSynchronousRequest: request
returningResponse: nil error: nil];
//serialize to JSON
NSDictionary *result = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableContainers error:nil];
//parsing JSON
bool success = [result[@"success"] boolValue];
if(success){
NSLog(@"Success=%@",result[@"msg"]);
}else{
NSLog(@"Fail=%@",result[@"msg"]);
}
And it works fine when connected to the internet but when it is not I get the error:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'data parameter is nil'
if (!returnData){
return; // or handle no connection error here
}else{
NSDictionary *result = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableContainers error:nil];
//parsing JSON
bool success = [result[@"success"] boolValue];
if(success){
NSLog(@"Success=%@",result[@"msg"]);
}else{
NSLog(@"Fail=%@",result[@"msg"]);
}
}
You have to check for connectivity before performing network request.
Once you have downloaded and imported Reachbility.m
and Reachbility.h
files
create a helper function:
-(BOOL)IsConnected{
Reachability *reachability = [Reachability reachabilityForInternetConnection];
NetworkStatus networkStatus = [reachability currentReachabilityStatus];
return !(networkStatus == NotReachable);
}
Then use it
if([self IsConnected]){
//connected!
//upload your image
}
else{
//not connected to internet!
}
Very important
If your project is not using arc
-fno-objc-arc
The app is crashing on this line
NSDictionary *result = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableContainers error:nil];
because the value of returnData is nil. All you need to do is test if this object is nil before passing into NSJSONSerialization like so
NSData* returnData = [NSURLConnection sendSynchronousRequest: request
returningResponse: nil error: nil];
if (returnData == nil)
{
// Handle No Data returned from server
// This can happen from no internet connection, from a server error or many other things
}
else
{
// Parse the Data
NSDictionary *result = [NSJSONSerialization JSONObjectWithData:returnData options:NSJSONReadingMutableContainers error:nil];
//parsing JSON
bool success = [result[@"success"] boolValue];
if(success){
NSLog(@"Success=%@",result[@"msg"]);
}else{
NSLog(@"Fail=%@",result[@"msg"]);
}
}
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