使用计时器检测按键

Question

Code:

    private void sprites_updater_Tick(object sender, EventArgs e)
    {
        s++;
        int x = player.Location.X;
        int y = player.Location.Y;
        if (s == 1)
      if (ModifierKeys.HasFlag(Keys.A))
            {
                player.Location = new Point(x - 5, y);
            }
            s = 0;
            sprites_updater.Start();

        }

So while using timer code, I wrote the same thing above (ModifierKeys.HasFlag(Keys.A)) but it didn´t work. Why?! BTW, is there any way to show a 3d camera perspective inside a WinForms Panel WITHOUT USING XNA, WPF or any other stuff (only .NET)?!

Answer 1

The best way to get keyboard strokes and processing them later is to catch the Keyboards events in the form using both KeyDown, KeyUp and flags:

bool isAPressed;
...

private void Form1_KeyDown(object sender, KeyEventArgs e)
{
    switch(e.KeyCode)
    {
        case Key.A:
            isAPressed = true;
            break;
        case Key.XXXX:
            ...
    }
}

private void Form1_KeyUp(object sender, KeyEventArgs e)
{
    switch(e.KeyCode)
    {
        case Key.A:
            isAPressed = false;
            break;
        case Key.XXXX:
            ...
    }
}

Then you can use this information in your timer :

private void sprites_updater_Tick(object sender, EventArgs e)
{
    s++;
    int x = player.Location.X;
    int y = player.Location.Y;
    if (s == 1)
    if (isAPressed)
        {
            player.Location = new Point(x - 5, y);
        }
        s = 0;
        sprites_updater.Start();
    }

This is particularily interresting to handle player moves this way (arrows).