Question

I need to remove the last character if the textfield length exceeds 100,I used the following code:

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if(textfield.text.length>=100)
    {
        NSString *text;
        textField.text=text;
        NSString *newString = [text substringToIndex:[text length]-1];
        textField.text=newString;
    }
    return YES;
}

But it just erases the whole text.

Answer 1

You erase the whole text because of this line:

textField.text=text; // text is nil here

What you wanted to do is more likely the following:

NSString *text = textField.text;