Set UITextField Maximum Length [duplicate]

Question

Is there any way to set the maximum length on a UITextField?

Something like the MAXLENGTH attribute in HTML input fields.

Answer 1

This works correctly with backspace and copy & paste:

#define MAXLENGTH 10  - (BOOL)textField:(UITextField *) textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {      NSUInteger oldLength = [textField.text length];     NSUInteger replacementLength = [string length];     NSUInteger rangeLength = range.length;      NSUInteger newLength = oldLength - rangeLength + replacementLength;      BOOL returnKey = [string rangeOfString: @"\n"].location != NSNotFound;      return newLength <= MAXLENGTH || returnKey; } 

UPDATE: Updated to accept the return key even when at MAXLENGTH. Thanks Mr Rogers!

Answer 2

UPDATE

I cannot delete this answer because it is the accepted one, but it was not correct. Here is the correct code, copied from TomA below:

#define MAXLENGTH 10  - (BOOL)textField:(UITextField *) textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {      NSUInteger oldLength = [textField.text length];     NSUInteger replacementLength = [string length];     NSUInteger rangeLength = range.length;      NSUInteger newLength = oldLength - rangeLength + replacementLength;      BOOL returnKey = [string rangeOfString: @"\n"].location != NSNotFound;      return newLength <= MAXLENGTH || returnKey; } 

ORIGINAL

I think you mean UITextField. If yes, then there is a simple way.

1. Implement the UITextFieldDelegate protocol
2. Implement the textField:shouldChangeCharactersInRange:replacementString: method.

That method gets called on every character tap or previous character replacement. in this method, you can do something like this:

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {     if ([textField.text length] > MAXLENGTH) {         textField.text = [textField.text substringToIndex:MAXLENGTH-1];         return NO;     }     return YES; }