Ios UITextField没有最大字符限制的空格

我有两个uitextfield：usernameField和passwordField。对于这两个字段，我试图实现下面的代码，以不允许用户键入任何空白（使用空格键），并限制每个文本字段的最大长度。空格的代码工作正常，但Max Length失败

//Addressing White space and length in the form
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

NSString *resultingString = [textField.text stringByReplacingCharactersInRange: range withString: string];
NSCharacterSet *whitespaceSet = [NSCharacterSet whitespaceCharacterSet];
if  ([resultingString rangeOfCharacterFromSet:whitespaceSet].location == NSNotFound)      {
    return YES;
}  else  {
    self.title.text = @"No Spaces Allowed";
    self.title.textColor = [UIColor yellowColor];
    return NO;
}


if (textField == self.usernameField)
{
    NSInteger MAXLENGTH = 15;

    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;

if (textField == self.passwordField)
    {
        NSInteger MAXLENGTH = 10;

        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;   
    }
}
}

//在表单中寻址空白和长度
-（BOOL）textField:（UITextField*）textField应更改字符范围：（NSRange）范围替换字符串：（NSString*）字符串{
NSString*resultingString=[textField.text StringByReplacingCharactersRange:range with string:string]；
NSCharacterSet*whitespaceSet=[NSCharacterSet-whitespaceCharacterSet]；
if（[resultingString rangeOfCharacterFromSet:whitespaceSet].location==NSNotFound）{
返回YES；
}否则{
self.title.text=@“不允许使用空格”；
self.title.textColor=[UIColor yellowColor]；
返回否；
}
if（textField==self.usernameField）
{
NSInteger最大长度=15；
NSU整数oldLength=[textField.text length]；
NSU整数替换长度=[字符串长度]；
NSU整数rangeLength=range.length；
NSUInteger newLength=oldLength-rangeLength+replacementLength；
BOOL returnKey=[string rangeOfString:@“\n”]。位置！=NSNotFound；
返回newLength以允许最大字符数并拒绝空格

执行
应更改范围内的字符委托

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    BOOL _isAllowed = YES;

    NSString *tempString = [[textField.text stringByReplacingCharactersInRange:range withString:string] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];


    if ([self.yourTextFeildName.text isEqualToString:tempString] || [tempString length] > 5)
    {
        _isAllowed =  NO;
    }

    return   _isAllowed;
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
   if ([textField.text length] < 5)
   {
         //text field length is less than 5.
   }
}

用于最小字符数

执行
textfielddendediting委托

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    BOOL _isAllowed = YES;

    NSString *tempString = [[textField.text stringByReplacingCharactersInRange:range withString:string] stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];


    if ([self.yourTextFeildName.text isEqualToString:tempString] || [tempString length] > 5)
    {
        _isAllowed =  NO;
    }

    return   _isAllowed;
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
   if ([textField.text length] < 5)
   {
         //text field length is less than 5.
   }
}

-（void）textfieldDendediting:（UITextField*）textField
{
如果（[textField.text length]<5）
{
//文本字段长度小于5。
}
}