View source for Raw key events

The built-in os has a function to read incoming keystrokes. But it also implements the functions to move the cursor while typing. This is not always a desired feature; imagine a case in which you want to make a menu with a controllable cursor around the menu entries. The current read() function won't let you.

==Detecting keystrokes==
In case I made you think the OS sucks, it doesn't (all the time). Because this OS is not Windows, we can access lower-level functions, such as os.pullEvent(). And that's the one that we're going to use:
<pre>
function rawread()
    bRead = true
    while(bRead) do
        local sEvent, param = os.pullEvent("key")
        if(sEvent == "key") then
            break
        end
    end
end
</pre>
This function waits for any key, then exits.

==Figuring out the key==
We can detect any key, but not which key. To find it out, we have to add some further logic to the code:
<pre>
function rawread()
    while true do
        local sEvent, param = os.pullEvent("key")
        if sEvent == "key" then
            if param == 28 then
                print("Enter detected")
                break
            end
        end
    end
end
</pre>
This function waits for the Enter key to be pressed. If so, it writes "Enter detected" to the screen and exits.

==Key scan codes ==
The scan codes are typical DirectX numbers.
{|
|style="vertical-align: top"|
{| border="1" cellpadding="5" cellspacing="0"
|-
! |Key
! |Code
|-
| Escape
| 1
|-
| 1
| 2
|-
| 2
| 3
|-
| 3
| 4
|-
| 4
| 5
|-
| 5
| 6
|-
| 6
| 7
|-
| 7
| 8
|-
| 8
| 9
|-
| 9
| 10
|-
| 0
| 11
|-
| Minus
| 12
|-
| Equals
| 13
|-
| Backspace
| 14
|-
| Tab
| 15
|-
| Q
| 16
|-
| W
| 17
|-
| E
| 18
|-
| R
| 19
|-
| T
| 20
|-
| Y
| 21
|-
| U
| 22
|-
| I
| 23
|-
| O
| 24
|-
| P
| 25
|}
|style="vertical-align: top"|
{| border="1" cellpadding="5" cellspacing="0"
|-
! |Key
! |Code
|-
| Left Bracket
| 26
|-
| Right Bracket
| 27
|-
| Enter
| 28
|-
| Left Control
| 29
|-
| A
| 30
|- 
| S
| 31
|-
| D
| 32
|-
| F
| 33
|-
| G
| 34
|-
| H
| 35
|-
| J
| 36
|-
| K
| 37
|-
| L
| 38
|-
| Semicolon
| 39
|-
| Apostrophe
| 40
|-
| Tilde (~)
| 41
|-
| Left Shift
| 42
|-
| Back Slash
| 43
|-
| Z
| 44
|-
| X
| 45
|-
| C
| 46
|-
| V
| 47
|}
|style="vertical-align: top"|
{| border="1" cellpadding="5" cellspacing="0"
|-
! |Key
! |Code
|-
| B
| 48
|-
| N
| 49
|-
| M
| 50
|-
| Comma
| 51
|-
| Period
| 52
|-
| Forward Slash
| 53
|-
| Right Shift
| 54
|-
| Numpad *
| 55
|-
| Left Alt
| 56
|-
| Spacebar
| 57
|-
| Caps Lock
| 58
|-
| F1
| 59
|-
| F2
| 60
|-
| F3
| 61
|-
| F4
| 62
|-
| F5
| 63
|-
| F6
| 64
|-
| F7
| 65
|-
| F8
| 66
|-
| F9
| 67
|-
| F10
| 68
|}
|style="vertical-align: top"|
{| border="1" cellpadding="5" cellspacing="0"
|-
! |Key
! |Code
|-
| Num Lock
| 69
|-
| Scroll Lock
| 70
|-
| Numpad 7
| 71
|-
| Numpad 8
| 72
|-
| Numpad 9
| 73
|-
| Numpad -
| 74
|-
| Numpad 4
| 75
|-
| Numpad 5
| 76
|-
| Numpad 6
| 77
|-
| Numpad +
| 78
|-
| Numpad 1
| 79
|-
| Numpad 2
| 80
|-
| Numpad 3
| 81
|-
| Numpad 0
| 82
|-
| Numpad .
| 83
|-
| F11
| 87
|-
| F12
| 88
|-
| Numpad Enter
| 28 <s>156</s> *
|-
| Right Control
| 157
|-
| Numpad /
| 181
|-
| Right Alt
| 184
|}
|style="vertical-align: top"|
{| border="1" cellpadding="5" cellspacing="0"
|-
! |Key
! |Code
|-
| Home
| 199
|-
| Up Arrow
| 200
|-
| Page Up
| 201
|-
| Left Arrow
| 203
|-
| Right Arrow
| 205
|-
| End
| 207
|-
| Down Arrow
| 208
|-
| Page Down
| 209
|-
| Insert
| 210
|-
| Delete
| 211
|-
| Left Super
| 219
|-
| Right Super
| 220
|-
| Menu
| 221
|-
|}
|}
Source: [http://wiki.tesnexus.com/index.php/DirectX_Scancodes_And_How_To_Use_Them Nexus Wiki]<br />
<i>Note: Items marked with * are not the correct keycode, but return a matching keycode for another button (eg, enter keys).</i>

[[Category:Tutorials]]