Question

I want to send json service when the user search text on searchbar. Here the issue is that I return null value of NSData object, what the issue is here? If I define the same url which I print in console that works but what’s the issue here?

-(void)doIt{

    NSURL *url = [NSURL URLWithString:weburls];
    NSData *data =[NSData dataWithContentsOfURL:url];
    [self getData:data];
}

If I will write like that then it works, but I want to call the service on the searchbar event but there is a problem

NSString *weburl = [NSString stringWithFormat:@"%@%@",
@"http://192.168.1.196/ravi/iphonephp?mname=",searchText];
NSLog(@"%@",weburl);

NSURL *url = [NSURL URLWithString:weburl];
NSLog(@"the url is : %@",url);

NSError *error;

NSData *data =[NSData dataWithContentsOfURL:url options:nil error:&error];
NSLog(@"Data is :%@",data);

NSLog(@"the Error massage is : %@",error);
[self getData:data];

Gives me console value like

customCellDemo[1553:f803] the url is : http://192.168.1.196/ravi/iphonephp?mname=a

2012-03-16 15:26:36.259 customCellDemo[1553:f803] Data is :(null)

2012-03-16 15:26:43.624 customCellDemo[1553:f803] the Error massage is : Error 
Domain=NSCocoaErrorDomain Code=256 "The operation couldn’t be completed. (Cocoa error 256.)" 
UserInfo=0x6ab2760 {NSURL=http://192.168.1.196/ravi/iphonephp?mname=a}

Answer 1

From the manual of dataWithContentsOfURL;

Return Value: A data object containing the data from the location
specified by aURL. Returns nil if the data object could not be
created.

In other words, it can either not create an NSData (unlikely) or it can probably not get any data from your supplied URL. I suggest you try to use dataWithContentsOfURL:options:error: instead to get an error code and be able to diagnose the problem.