//还可以输入的长度。

- (void)textViewDidChange:(UITextView *)textView

{

    UITextRange *markRange = textView.markedTextRange;

    int pos = [textView offsetFromPosition:markRange.start

                              toPosition:markRange.end];

    int nLength = textView.text.length - pos;

    if (nLength > 15 && pos == 0)

    {

         _limit.text = [NSString stringWithFormat:@"%d/%@",15,@"15"];

        _nickTextView.text = [textView.text substringToIndex:15];

    }

    else if(nLength <= 15 && pos == 0)

    {

         _limit.text = [NSString stringWithFormat:@"%d/%@",[textView.text length],@"15"];

    }

}