objective-c - UITextView，如何删除返回键 :linefeed?

Question

我想删除按回车键输入的换行符。但是当我执行以下操作时，它会从文本中删除最后一个字符。为什么？

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;
{
    NSLog(@"%d  %d  %@ %@",range.location,range.length, text, [textView text]);

    if ( [text isEqualToString:@"\n"] ) {

        NSString *s = [textView text];
        s = [s substringToIndex:[s length] - 1]; // <------------

        [tvText setText:[NSString stringWithFormat:@"%@\n>>",s]];
    }
    return YES;
}

---

我希望结果看起来像:

>>name
>>yoda
>>                <---- cursor is moved to the right of ">>"

Answer 1

我认为你可以做这样的事情，

    - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;
{
    NSLog(@"%d  %d  %@ %@",range.location,range.length, text, [textView text]);

    if ( [text isEqualToString:@"\n"] ) {

        [tvText setText:[NSString stringWithFormat:@"%@\n>>",tvText.text]];
        return NO;
    }
    return YES;
}