IOS开发中限制TextField输入的类型及长度的方法

- (BOOL)textField:(UITextField *)textField 
shouldChangeCharactersInRange:(NSRange)range 
replacementString:(NSString *)string{

	// Check for non-numeric characters
	NSUInteger lengthOfString = string.length;
	for (NSInteger loopIndex = 0; loopIndex < lengthOfString; loopIndex++) {
    	unichar character = [string characterAtIndex:loopIndex];
    	if (character < 48) return NO; // 48 unichar for 0
    	if (character > 57) return NO; // 57 unichar for 9
	}

	// Check for total length
	NSUInteger proposedNewLength = 
	textField.text.length - range.length + string.length;
	
	if (proposedNewLength > 11)
    	return NO;//限制长度
    	
	return YES;
}


摘自CSDN