iOS 获取软键盘高度

- (void)viewDidLoad{

       [[NSNotificationCenterdefaultCenter] addObserver:self selector:@selector(keyboardDidShow:)

                name :UIKeyboardDidShowNotification object:nil];  

       [[NSNotificationCenterdefaultCenter] addObserver:self selector:@selector(keyboardDidHide:)

                name :UIKeyboardDidHideNotification   object:nil];

}

- (void)keyboardDidShow:(NSNotification *)nsNotification {

         NSDictionary *userInfo = [nsNotificationuserInfo]; 

         _keyboardSize = [[userInfo  objectForKey : UIKeyboardFrameBeginUserInfoKey ]   CGRectValue ]. size ;

        [ self updateTextViewSize];

}

- (void)keyboardDidHide:(NSNotification *)nsNotification {

          _keyboardSize =CGSizeMake(0.0,0.0);

         [ self updateTextViewSize];

}

- (void)updateTextViewSize {

         UIInterfaceOrientation orientation =

         [UIApplicationsharedApplication].statusBarOrientation;

         CGFloat keyboardHeight =    UIInterfaceOrientationIsLandscape (orientation) ?    _keyboardSize . width          

                                                               : _keyboardSize . height ;

          _textView.frame =CGRectMake(0, 0,   self . view . frame . size . width ,   self . view . frame . size . height - keyboardHeight);

}

原文：http://blog.csdn.net/leochang130731/article/details/22874263