Pass a variable to a field

This is the main script code, located C: \ Program Files (x86) \ Adobe \ Acrobat DC \ Acrobat \ Javascripts

app.addMenuItem({ cParent:"Help", cName:"-", cExec:" ", nPos: 0});
app.addMenuItem({ cParent: "Help", cUser: "Test", cName: "Test", cExec: "Test()", cEnable: "event.rc = (event.target != null);",  nPos: 0});

function Test() 
{
var dialog1 = 
{
	Btn1: function(dialog)
	{
		var result = dialog.store()["Txt1"]
		Ndata = result
		dialog.end("Btn1");
	},
	Stop: function(dialog)
	{	
		idx = "Cancel"
		dialog.end("Stop");
	},
	description:
	{name: "Test", align_children: "row", width: 300, height: 300,
		elements:
		[
			{
				alignment: "align_right",
				type: "button",
				name: "Cancel",
				item_id: "Stop",
				width: 5
			},
			{
				type: "edit_text",
				item_id: "Txt1",
				width: 170,
				height: 25
			},
			{
				type: "button",
				name: "Enter date",
				item_id: "Btn1",
			}
		]
	}
};
app.execDialog(dialog1);

		array = this.getPageBox("Crop",1);
		r = array.toString()
		r = r.split(",");
		rectX1 = [Math.round(r[2])-391, 108, Math.round(r[2])-354, 132];
		this.addAnnot({page: 1, type: "Stamp", rect: rectX1, author: "", AP: "#NewDate" })

}; app.trustedFunction(Test);

  Stamp template located C: \ Users \ 1 \ AppData \ Roaming \ Adobe \ Acrobat \ DC \ Stamps