HTTP POST request in iOS [closed] - ios

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hi i am new in ios and i didn't send any call to php till now today i have tried by the following code
-(void)sendRequest
{
NSString *vali = #"$uppl!3r$";
NSString *post = [NSString stringWithFormat:#"key1=%#",vali];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
NSLog(#"%#",postLength);
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:#"http://www.ddemo3.enerjinet.com/webservices/ios/suppliers.php"]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if (theConnection) {
webData = [[NSMutableData data] retain];
NSLog(#"%#",webData);
}
else
{
}
}
-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[webData setLength: 0];
}
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[webData appendData:data];
}
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
[connection release];
[webData release];
}
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSString *loginStatus = [[NSString alloc] initWithBytes: [webData mutableBytes] length: [webData length] encoding:NSUTF8StringEncoding];
NSLog(#"%#",loginStatus);
//greeting.text = loginStatus;
[loginStatus release];
[connection release];
[webData release];
}
it should return me array of 76 records but it returns me <> can anyone please help me ? The web service is ready i need to get the array in response and show it in my table view please help me in doing this

Answer 1

A couple of thoughts:
You NSLog your webData, which will always show <> (as your logging it immediately after instantiated it). I'm not sure why you're logging that.
The question is whether you're seeing that <>, or the NSLog in connectionDidFinishLoading.
I ask that because you are not logging the error in connection:didFailWithError:, if it fails, you'll never know why. You really should log the error in connection:didFailWithError: so you know if it failed, and if so, why:
NSLog(#"%s: %#", __FUNCTION__, error);
In your connection:didReceiveResponse:, you really should look at the HTTP status code:
if ([response isKindOfClass:[NSHTTPURLResponse class]]) {
NSInteger statusCode = [(NSHTTPURLResponse *)response statusCode];
if (statusCode != 200)
NSLog(#"%s: status code is %d; should be 200", __FUNCTION__, statusCode);
}
If it's not 200, you really want to know about that.
You report in one of your comments that you are seeing connectionDidFinishLoading: called, but never having didReceiveData called. That means (unsurprisingly) that there was no data received. So, you should:
Confirm that the connection:didReceiveResponse: reported a statusCode of 200; and
Confirm that the server code is working properly. I could imagine getting the behavior you describe if you had an error in your server PHP code (which is exacerbated by the fact that servers often have display_errors turned off in their php.ini file).
As an aside, if it's possible that the value associated with key1 might contain any reserved characters (as defined in section 2 of RFC 3986), you should percent-escape the string using CFURLCreateStringByAddingPercentEscapes. Thus:
NSString *post = [NSString stringWithFormat:#"key1=%#", [self percentEscapeString:vali]];
Where, per the W3C specs for application/x-www-form-urlencoded, you not only percent escape, but also replace spaces with + characters, thus:
- (NSString *)percentEscapeString:(NSString *)string
{
NSString *result = CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
(CFStringRef)string,
(CFStringRef)#" ",
(CFStringRef)#":/?#!$&'()*+,;=",
kCFStringEncodingUTF8));
return [result stringByReplacingOccurrencesOfString:#" " withString:#"+"];
}

Answer 2

Use:
+ (void)sendAsynchronousRequest:(NSURLRequest *)request queue:(NSOperationQueue *)queue completionHandler:(void (^)(NSURLResponse*, NSData*, NSError*))handler
Unless you have a compelling reason not to.
Example (probably non-working):
Note creating postData.
-(void)sendRequest {
NSString *vali = #"$uppl!3r$";
NSString *post = [NSString stringWithFormat:#"key1=%#",vali];
NSData *postData = [post dataUsingEncoding:NSUTF8StringEncoding];
NSString *postLength = [NSString stringWithFormat:#"%lu", [postData length]];
NSLog(#"%#", postLength);
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:#"http://www.ddemo3.enerjinet.com/webservices/ios/suppliers.php"]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
NSLog(#"data: %#", data);
}];
}
Oh, make life easier, use ARC.