KeyboardState oldState = Keyboard.GetState();
protected override void Update( GameTime gameTime )
{
// Allows the default game to exit on Xbox 360 and Windows
if (GamePad.GetState( PlayerIndex.One ).Buttons.Back == ButtonState.Pressed)
this.Exit();
UpdateInput();
base.Update( gameTime );
}
private void UpdateInput()
{
KeyboardState newState = Keyboard.GetState();
// Check to see whether the Spacebar is down.
if (newState.IsKeyDown( Keys.Space ))
{
// Key has just been pressed.
}
// Otherwise, check to see whether it was down before.
// (and therefore just released)
else if (oldState.IsKeyDown( Keys.Space ))
{
// Key has just been released.
}
oldState = newState;
}
[.net] question using case: for input (XNA)
Author
Hi, im developping my own game atm, and im writing the input part at the moment. I've found code to show me how to implement keyboard input:
Now in my game i want to use the spacebar, the up and down arrow, and the ctrl button.
So it would be stupid to write if statements for them all,
so i want to use the "case:" statement.
The only problem is that i dont know what parameter to give it for each button.
("case newState.IsKeyDown(Keys.Space):" doesn't work).
Im fairly new at this, but if anyone could help me out with this i'd be very thankfull.
Are you saying the player is only allowed to use one key at a time? If not then you wouldn't use a switch block, the if statements are the way to go. Also, your check for a key being pressed is slight incorrect. To check for a key just being pressed you would do:
if (newState.IsKeyDown( Keys.Space ) && !oldState.IsKeyDown( Keys.Space )){ // Key has just been pressed.}
The way I do it is a little different.
I use a map<> of delegates to the functions. It makes it easier to manage then a monolithic switch or if block, at least to me.
theTroll
I use a map<> of delegates to the functions. It makes it easier to manage then a monolithic switch or if block, at least to me.
theTroll
Quote:Original post by TheTroll
The way I do it is a little different.
I use a map<> of delegates to the functions. It makes it easier to manage then a monolithic switch or if block, at least to me.
theTroll
Agreed. For someone just starting out though, understanding the basics is probably a good thing. Also, if the game is only 4 keys it's not a big deal IMO. [grin]
Author
so eehm the idea is that up and down are not pressed simutaniously, but ctrl and space or keyarrow + space might be pressed simultaniously.
should i stick to the if statements?
maybe some1 can make show an example using case's :)
Thanks for the input guys.
should i stick to the if statements?
maybe some1 can make show an example using case's :)
Thanks for the input guys.
Using a switch to check the keyboard means that you'll kick out of the switch when it hits the first check that evaluates to true. So if you're checking for firing a weapon first and moving second you'll never hit the moving check if you're firing the weapon. The same thing done with ifs:
You don't have that problem.
if (newState.IsKeyDown(Keys.Escape) && _oldState.IsKeyDown(Keys.Escape)) { this.Exit(); } if (newState.IsKeyDown(Keys.Space) && _oldState.IsKeyDown(Keys.Space)) { //fire weapon } if (newState.IsKeyDown(Keys.Left) && _oldState.IsKeyDown(Keys.Left)) { //move left }You don't have that problem.
Author
thanks alot, i totally realise that i cant use case now thanks :)
ill give you a hint when the game is done if you like, thanks for the help again all!
ill give you a hint when the game is done if you like, thanks for the help again all!
Actually you can continue to use case statements.
Call KeyboardState.GetPressedKeys();
which returns an array of Keys[] which you can parse and run through a switch.
I also use this to convert alot of keys (Keys is a large enum) to their ascii version.
string letter = Keys.A.ToString();
Of course you will have to filter out and catch special keys but it beats having to filter out 105+ keys.
Call KeyboardState.GetPressedKeys();
which returns an array of Keys[] which you can parse and run through a switch.
I also use this to convert alot of keys (Keys is a large enum) to their ascii version.
string letter = Keys.A.ToString();
Of course you will have to filter out and catch special keys but it beats having to filter out 105+ keys.
Author
Thanks again, i tryed to use it but i failed :P
anyway, i used the following code to fix it atm:
i realised i used too much code i didn't need :)
anyway, i used the following code to fix it atm:
#region down// Is the down-arrow key down?if (newState.IsKeyDown(Keys.Down)){ fanPosition += moveFactorPerSecond;}else if (oldState.IsKeyDown(Keys.Down)){ // Key was down last update, but not down now, so // it has just been released. }#endregioni realised i used too much code i didn't need :)
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