键盘高度

//当键盘出现或改变时调用

- (void)keyboardWillShow:(NSNotification *)aNotification

{

    //获取键盘的高度

NSDictionary *userInfo =

[aNotification userInfo];

    NSValue

*aValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];

CGRect keyboardRect = [aValue

CGRectValue];

self.keyboardHeight

= keyboardRect.size.height;

}