NSURL not initialized with mutable string

verbatimbot · 06-10-2011, 07:31 AM

Hello,
I am trying to get a response from a webservice with simple

Code:

NSString *strData = [NSString  stringWithContentsOfURL:url];

but NSUrl never gets initialized - I am appending parameters to mutable string. If I hardcode values with single @"url-with-parameters" everything goes ok.
Must say I'm beginner in obj-c programming.

Code:

NSMutableString *urlString = [[NSMutableString alloc] initWithString:@"http://www.someurl.com/httphandlers/iphonedatastore.ashx?mode=contact"];
    [urlString appendString:@"&name="];
    [urlString appendString:txtName.text];
    [urlString appendString:@"&msg="];
    [urlString appendString:txtMessage.text];
    [urlString appendString:@"&email="];
    [urlString appendString:txtEmail.text];
    [urlString appendString:@"&subj="];
    [urlString appendString:txtSubject.text];
    
    NSURL *url = [[NSURL alloc] initWithString:urlString];

Thanks in advance

Duncan C · 06-10-2011, 04:24 PM

Quote:

Originally Posted by verbatimbot

Hello,
I am trying to get a response from a webservice with simple

Code:

NSString *strData = [NSString  stringWithContentsOfURL:url];

but NSUrl never gets initialized - I am appending parameters to mutable string. If I hardcode values with single @"url-with-parameters" everything goes ok.
Must say I'm beginner in obj-c programming.

Code:

NSMutableString *urlString = [[NSMutableString alloc] initWithString:@"http://www.someurl.com/httphandlers/iphonedatastore.ashx?mode=contact"];
    [urlString appendString:@"&name="];
    [urlString appendString:txtName.text];
    [urlString appendString:@"&msg="];
    [urlString appendString:txtMessage.text];
    [urlString appendString:@"&email="];
    [urlString appendString:txtEmail.text];
    [urlString appendString:@"&subj="];
    [urlString appendString:txtSubject.text];
    
    NSURL *url = [[NSURL alloc] initWithString:urlString];

Thanks in advance

I'm pretty sure that the string has to represent a legal URL or the call to initWithString will fail and return nil.

If I had to guess, I would say that some of the text you are using to build your URL contains spaces or other illegal characters.

You are asking for SERIOUS trouble if you pass user-entered text directly into a URL without checking it and escaping special characters.

I don't have time at the moment, but I can dig up code I've used in the past to take user input and escape it for including in a URL.

Remember, characters like "&", "=", "/" "@" and of course space, are all special in a URL and have to be handled differently.

verbatimbot · 07-04-2011, 09:32 AM

nice, thanks for replying