Question-C # form received in the arrow keys do not work

 

 

Form uses event Form1_KeyDown , press the up and down keys on the keyboard do not respond.

 

Because Tab, Return, Esc and the up key, down key, left key and the right key is a pretreatment of these, when not used directly.

 

1         private void Form1_KeyDown(object sender, KeyEventArgs e)
2         {
3             //Keys NowKeys = Keys.Right;
4             this.NowKeys = e.KeyCode;
5         }

Like when doing the above, there will be no reaction.

This time need to use e.IsInputKey = true; this property;

The Properties button there, that is to say not take effect until the button is pressed.

1         private void Button1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
2         {
3             e.IsInputKey = true;
4         }

 

Now you need to set the form's KeyPreview property to True.

 

 

 More than ready to use.

There is another solution, which is the following:

. 1          ///  <Summary> 
2          /// override the default handling system keys, direction keys encountered, the process directly returns, not processed, so that the key will be transferred to the form, the trigger event KeyDown
 3          ///  </ Summary> 
. 4          ///  <param name = "the keyCode"> </ param> 
. 5          ///  <Returns> </ Returns> 
. 6          protected  the override  BOOL the ProcessDialogKey (Keys the keyCode)
 . 7          {
 . 8              IF (the keyCode == Keys. || || the keyCode == Keys.Down Up the keyCode == Keys.Left || the keyCode == Keys.Right)
 . 9                  return  to false ;
 10              the else 
. 11                  return  Base .ProcessDialogKey (the keyCode);
 12 is         }

This part of the code directly copied to the program which you can, do not need any special treatment.