get keyCode from string?

Question

Using a static method in as3, I can get a charCode from a character in a string.

How can I get the keyCode from a character in a string? Do I need to run this function through javascript (if I can do this in Javascript...)

Answer 1

Copy and paste as "KeyCodeUtil.as", put it under the folder: net/onthewings/utils

/*
    KeyCodeUtil.as

    Andy Li (andy@onthewings.net)
    2009-11-02  
*/

package net.onthewings.utils {
    import flash.ui.Keyboard;


    public class KeyCodeUtil {
        /*
            The below codes is used for generating KEYCODES. Some formating is needed to be done by hand after getting the outputStr.

            var outputStr:String = "";
            function onPress(evt:KeyboardEvent):void {
                outputStr += "'" + evt.charCode + "':" + evt.keyCode + ", //"+String.fromCharCode(evt.charCode)+"\n";
            }
        */
        static public const KEYCODES:Object = {
                27: 27,     //esc
                96: 192,    //`
                49: 49,     //1
                50: 50,     //2
                51: 51,     //3
                52: 52,     //4
                53: 53,     //5
                54: 54,     //6
                55: 55,     //7
                56: 56,     //8
                57: 57,     //9
                48: 48,     //0
                45: 189,    //-
                61: 187,    //=
                8: 8,       //backspace
                9: 9,       //tab
                113: 81,    //q
                119: 87,    //w
                101: 69,    //e
                114: 82,    //r
                116: 84,    //t
                121: 89,    //y
                117: 85,    //u
                105: 73,    //i
                111: 79,    //o
                112: 80,    //p
                91: 219,    //[
                93: 221,    //]
                92: 220,    //\
                97: 65,     //a
                115: 83,    //s
                100: 68,    //d
                102: 70,    //f
                103: 71,    //g
                104: 72,    //h
                106: 74,    //j
                107: 75,    //k
                108: 76,    //l
                59: 186,    //;
                39: 222,    //'
                13: 13,     //enter
                122: 90,    //z
                120: 88,    //x
                99: 67,     //c
                118: 86,    //v
                98: 66,     //b
                110: 78,    //n
                109: 77,    //m
                44: 188,    //,
                46: 190,    //.
                47: 191,    ///
                32: 32,     //space
                127: 46,    //delete
                126: 192,   //~
                33: 49,     //!
                64: 50,     //@
                35: 51,     //#
                36: 52,     //$
                37: 53,     //%
                94: 54,     //^
                38: 55,     //&
                42: 56,     //*
                40: 57,     //(
                41: 48,     //)
                95: 189,    //_
                43: 187,    //+
                81: 81,     //Q
                87: 87,     //W
                69: 69,     //E
                82: 82,     //R
                84: 84,     //T
                89: 89,     //Y
                85: 85,     //U
                73: 73,     //I
                79: 79,     //O
                80: 80,     //P
                123: 219,   //{
                125: 221,   //}
                124: 220,   //|
                65: 65,     //A
                83: 83,     //S
                68: 68,     //D
                70: 70,     //F
                71: 71,     //G
                72: 72,     //H
                74: 74,     //J
                75: 75,     //K
                76: 76,     //L
                58: 186,    //:
                34: 222,    //"
                90: 90,     //Z
                88: 88,     //X
                67: 67,     //C
                86: 86,     //V
                66: 66,     //B
                78: 78,     //N
                77: 77,     //M
                60: 188,    //<
                62: 190,    //>
                63: 191     //?
            }

        /**
         * @param char Can be String or charCode(Number).
         * @param numpad If set to true, the function will return the keyCode for numpad. Ignored if numpad have no such key.
         */
        static public function keyCodeOf(char:*, numpad:Boolean = false):Number {
            var charCode:Number;

            if (char is String)
                charCode = (char as String).charCodeAt();
            else
                charCode = char;

            if (numpad){
                if (charCode >= 48 && charCode <= 57){ //0-9
                    return charCode + 48;
                } else if (charCode == 43){
                    return Keyboard.NUMPAD_ADD;
                } else if (charCode == 46){
                    return Keyboard.NUMPAD_DECIMAL;
                } else if (charCode == 47){
                    return Keyboard.NUMPAD_DIVIDE;
                } else if (charCode == 13){
                    return Keyboard.NUMPAD_ENTER;
                } else if (charCode == 42){
                    return Keyboard.NUMPAD_MULTIPLY;
                } else if (charCode == 45){
                    return Keyboard.NUMPAD_SUBTRACT;
                }
            }

            return KEYCODES[charCode] ? KEYCODES[charCode] : -1;
        }

    }
}

Answer 2

Use this in Adobe AIR:

var str:String = "a"; //only one letter at a time
var keyCode:uint = Keyboard[str.toUpperCase()];
trace(keyCode);

Answer 3

Why are you getting the keycode from a string? Why not get it directly from the KeyboardEvent?

Below is a stripped down version of the sample code in the documentation that shows how to handle and retrieve the keycode from the KeyboardEvent:

package {
    import flash.display.Sprite;
    import flash.display.DisplayObject;
    import flash.events.*;

    public class KeyboardEventExample extends Sprite {
        private var child:Sprite = new Sprite();
        private var bgColor:uint = 0x00CCFF;
        private var size:uint = 80;

        public function KeyboardEventExample() {
            child.graphics.beginFill(bgColor);
            child.graphics.drawRect(0, 0, size, size);
            child.graphics.endFill();
            addChild(child);
            child.addEventListener(KeyboardEvent.KEY_DOWN, keyDownHandler);
            child.addEventListener(KeyboardEvent.KEY_UP, keyUpHandler);
        }

        private function keyDownHandler(event:KeyboardEvent):void {
            trace("keyDownHandler: " + event.keyCode);
        }

        private function keyUpHandler(event:KeyboardEvent):void {
            trace("keyUpHandler: " + event.keyCode);
        }
    }
}

Answer 4

If you really do have a string that needs to be read and listening to the keyboard is not an option (as Soviut suggests) then you will need to ensure the string is delimited some how, mostly likely with commas - as the number of characters is not the same for each keyCode, and some keyCodes are Strings while others are uint.

Here is a list of all the keyCode constants:

http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/flash/ui/Keyboard.html

Answer 5

I thought I'd include a much easier way to do this:

var str:String = "B";
trace(str.charCodeAt(0));  // replace 0 with the index of the char you want the code of