监听文字改变

1、监听UITextField文字的改变：

[textField addTarget:selfaction:@selector(textEditingChanged) forControlEvents:UIControlEventEditingChanged];

2、监听UITextView文字的改变：

（1）通知：

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onTextViewDidChange:) name:UITextViewTextDidChangeNotification object:nil];

- (void)onTextViewDidChange:(NSNotification *)aNotify

{

    UITextView *textView = aNotify.object;

}

（2）代理：

- (void)textViewDidChange:(UITextView *)textView;