Action that converts artboard to specific size [Letter Size]

Not the cleanest code, but it's operational...

var docRef = app.activeDocument;
var docRef = app.activeDocument;
var ABs = docRef.artboards;
var choice;
//Creates new Popup
var Pallette = new Window ("dialog", "Artboard Resizer");
Pallette.add ("statictext", undefined, "Pick a size");
Pallette.orientation = "row";
//Dropdown Menu
var myDropdown = Pallette.add ("dropdownlist", undefined, [
"8.5\" x 11\"",
"11\" x 8.5\"",
"12\" x 12\"",
"12\" x 16\"",
"16\" x 12\"",
"24\" x 12\"",
"32\" x 20\""
]);
myDropdown.selection = 0
var group3 = Pallette.add("group");
    group3.orientation = "row";
    //var a = group3.add("radiobutton", undefined, "Single Artboard");
    var a = group3.add("radiobutton", undefined, "All Artboards");
    var radiobuttons = [a];
    a.checkedState = false;
    for (var i = 0; i < radiobuttons.length; i++) {
    (function (i) {
        radiobuttons[i].onClick = function () {
            method = radiobuttons[i].text;
        };
    })(i);
 }

    var myButtonGroup =  Pallette.add ("group");
    myButtonGroup.orientation = "column";
    var btnCreate = myButtonGroup.add ("button", undefined, "OK");
    btnCreate.onClick = function () {
    choice = myDropdown.selection.text;
    method = radiobuttons[i].text;
    w.button.onClick = function () {

        w.close();
   
    }  
 };
Pallette.show ();

var method = method;

if(method == "All Artboards"){

    if (choice == "8.5\" x 11\"") {
        resizeAllArtboards(8.5 * 72, 11 * 72);
    } else if (choice == "11\" x 8.5\"") {
        resizeAllArtboards(11 * 72, 8.5 * 72);
    } else if (choice == "12\" x 12\"") {
        resizeAllArtboards(12 * 72, 12 * 72);
    } else if (choice == "12\" x 16\"") {
        resizeAllArtboards(12 * 72, 16 * 72);
    } else if (choice == "16\" x 12\"") {
        resizeAllArtboards(16 * 72, 12 * 72);
    } else if (choice == "24\" x 12\"") {
        resizeAllArtboards(24 * 72, 12 * 72);
    }  else if (choice == "32\" x 20\"") {
        resizeAllArtboards(32 * 72, 20 * 72);
    }}
else {
    // new code
    if (choice == "8.5\" x 11\"") {
        resizeArtboard(8.5 * 72, 11 * 72);
    } else if (choice == "11\" x 8.5\"") {
        resizeArtboard(11 * 72, 8.5 * 72);
    } else if (choice == "12\" x 12\"") {
        resizeArtboard(12 * 72, 12 * 72);
    } else if (choice == "12\" x 16\"") {
        resizeArtboard(12 * 72, 16 * 72);
    } else if (choice == "16\" x 12\"") {
        resizeArtboard(16 * 72, 12 * 72);
    } else if (choice == "24\" x 12\"") {
        resizeArtboard(24 * 72, 12 * 72);
    }  else if (choice == "32\" x 20\"") {
        resizeArtboard(32 * 72, 20 * 72);
    }
   
 }


function resizeAllArtboards(w, h) {
        for (var i = 0; i < ABs.length; i++) {
        app.selection = null;
        ABs.setActiveArtboardIndex(i);
        var idx  = docRef.artboards.getActiveArtboardIndex();
        var AB  = docRef.artboards[idx];
        var ABR = AB.artboardRect;
        var xC = ABR[0]+((ABR[2]-ABR[0])/2);
        var yC = ABR[1]+((ABR[3]-ABR[1])/2);
        AB.artboardRect = [xC-w/2, yC+h/2, xC+w/2, yC-h/2];
  }
 }

function resizeArtboard(w, h) {
    var idx  = docRef.artboards.getActiveArtboardIndex();
    var AB  = docRef.artboards[idx];
    var ABR = AB.artboardRect;
    var xC = ABR[0]+((ABR[2]-ABR[0])/2);
    var yC = ABR[1]+((ABR[3]-ABR[1])/2);
    AB.artboardRect = [xC-w/2, yC+h/2, xC+w/2, yC-h/2];
    }