就像matt对samvermette的评论一样，我也不喜欢检测“\n”的想法。返回键在UITextView中是有原因的，当然是去下一行。

在我看来，最好的解决方案是模仿iPhone的消息应用程序-这是在键盘上添加工具栏(和按钮)。

我从以下博客文章中得到了代码:

http://www.iosdevnotes.com/2011/02/iphone-keyboard-toolbar/

步骤:

-添加工具栏到你的XIB文件-设置高度为460

-添加工具栏按钮项(如果尚未添加)。如果需要右对齐，还可以将灵活的工具栏按钮项添加到XIB，并移动工具栏按钮项

-创建将按钮项目链接到resignFirstResponder的动作，如下所示:

- (IBAction)hideKeyboard:(id)sender {
    [yourUITextView resignFirstResponder];
}

套:

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];

    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];

    CGRect frame = self.keyboardToolbar.frame;
    frame.origin.y = self.view.frame.size.height - 260.0;
    self.keyboardToolbar.frame = frame;

    [UIView commitAnimations];
}

- (void)keyboardWillHide:(NSNotification *)notification {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];

    CGRect frame = self.keyboardToolbar.frame;
    frame.origin.y = self.view.frame.size.height;
    self.keyboardToolbar.frame = frame;

    [UIView commitAnimations];
}

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
    if([text isEqualToString:@"\n"])
        [textView resignFirstResponder];
    return YES;
}

yourtextView.delegate=self;

还要添加UITextViewDelegate

别忘了确认协议

如果你没有添加IF ([text isEqualToString:@"\n"])，你就不能编辑

-(BOOL)textFieldShouldReturn:(UITextField *)textField; // called from textfield (keyboard)

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text; // good tester function - thanks

我想我应该把这个片段放在这里:

确保声明了对UITextViewDelegate协议的支持。

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {

    if([text isEqualToString:@"\n"]) {
        [textView resignFirstResponder];
        return NO;
    }

    return YES;
}

Swift 4.0更新:

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    if text == "\n" {
        textView.resignFirstResponder()
        return false
    }
    return true
}

试试这个。

NSInteger lengthOfText = [[textView.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length];

斯威夫特

func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
    if text == "\n" {
        textView.resignFirstResponder()
    }
    return true
}