Comments on: Validate User Input in UITextField, with Smarts to Properly Manage Copy and Paste http://MobileDeveloperTips.com/user-interface/validate-user-input-in-uitextfield-with-smarts-to-properly-manage-copy-and-paste.html iOS and Objective-C Tips, Tricks and Tutorials. Tue, 22 May 2012 11:53:47 -0500 hourly 1 http://wordpress.org/?v=3.3.2 By: Bruno http://MobileDeveloperTips.com/user-interface/validate-user-input-in-uitextfield-with-smarts-to-properly-manage-copy-and-paste.html#comment-67792 Bruno Wed, 29 Feb 2012 08:22:27 +0000 http://iPhoneDeveloperTips.com/?p=5580#comment-67792 Thanks John, it helped me a lot ! Thanks John, it helped me a lot !

]]> By: Scott Marks http://MobileDeveloperTips.com/user-interface/validate-user-input-in-uitextfield-with-smarts-to-properly-manage-copy-and-paste.html#comment-25710 Scott Marks Tue, 14 Sep 2010 21:13:25 +0000 http://iPhoneDeveloperTips.com/?p=5580#comment-25710 Nice not. Two things -- First, the concatenation of two constant strings can be done at compile time without resort to stringByAppendingString:. Just write them one after another, just like regular strings in C. #define CHARACTERS_NUMBERS CHARACTERS @"1234567890" For extra tidiness, you could enclose the definition in parentheses, but as above you could concatenate yet more things onto CHARACTERS_NUMBERS. Second, I have a problem with if ( something ) return NO; else return YES; That is just simply return !(something). So in this case: return [[string componentsSeparatedByCharactersInSet:unacceptedInput] count] == 1; This makes the condition being asserted even more clear. Nice not. Two things –

First, the concatenation of two constant strings can be done at compile time without resort to stringByAppendingString:. Just write them one after another, just like regular strings in C.

#define CHARACTERS_NUMBERS CHARACTERS @”1234567890″

For extra tidiness, you could enclose the definition in parentheses, but as above you could concatenate yet more things onto CHARACTERS_NUMBERS.

Second, I have a problem with if ( something ) return NO; else return YES; That is just simply
return !(something). So in this case:

return [[string componentsSeparatedByCharactersInSet:unacceptedInput] count] == 1;

This makes the condition being asserted even more clear.

]]> By: John Muchow http://MobileDeveloperTips.com/user-interface/validate-user-input-in-uitextfield-with-smarts-to-properly-manage-copy-and-paste.html#comment-10275 John Muchow Mon, 01 Mar 2010 16:52:19 +0000 http://iPhoneDeveloperTips.com/?p=5580#comment-10275 Thanks Michelle, good catch, I've updated the code example based on your tip. Thanks Michelle, good catch, I’ve updated the code example based on your tip.

]]> By: Michelle http://MobileDeveloperTips.com/user-interface/validate-user-input-in-uitextfield-with-smarts-to-properly-manage-copy-and-paste.html#comment-10272 Michelle Mon, 01 Mar 2010 15:54:06 +0000 http://iPhoneDeveloperTips.com/?p=5580#comment-10272 After this step: "The result returned is an array of objects that have been divided by the invalid characters." -- why not just check if ([array count > 1) ? If invalid characters are found, won't there be 2 or more objects in the array? After this step: “The result returned is an array of objects that have been divided by the invalid characters.” — why not just check if ([array count > 1) ? If invalid characters are found, won’t there be 2 or more objects in the array?

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