can i connect keystrokes directly to functions?

Hi Experts, i wonder if i can connect keystrokes directly to functions instead of double click or (run) the script everytime with UI , i mean can i run script once and call the functions via keystrokes instead of showing Script UI that need to be Active to respond? and thanks in advance

#targetengine "mysession";
var w = new Window("palette", {independent:true});
w.orientation = "stack"
w.alignment = "center"

var edit = w.add ("edittext")
edit.visible = false
edit.active = true;

w.text = "Send KeyStrokes to Execute Functions"
w.preferredSize.width = 200;
w.alignChildren = ["left", "top"]; 
w.orientation = "row"; 
w.spacing = 5;
w.margins = 16
w.add ("statictext", undefined,"Send KeyStrokes to Execute Functions");

w.show();

w.addEventListener ("keydown", function keyPressed(key){
    switch (key.keyName) {
        case "U":
        PressU();
        case "V":
        PressV();
        case "H":
        PressH();
        case "M":
        PressM();
        case "Escape":
        w.close()
    }
})