Maintaining dynamic textbox control values into an array in javascript onchange event

I need to maintain text box values into an array in javascript onchange event. The text box control is created dynammically in javascript function. I have used below code. But at the end the array contains current element only. Previous values are not maintaining. How can I maintain textbox value each time entered.

<script type="text/javascript" language="javascript">

function DrawTextBox(j) {

    var imgElement = document.getElementById('myimage');

    var imgCoord = imgElement.getBoundingClientRect();

    var cl = imgCoord.left + 20;

    var x = x - cl;

    var y = y - imgCoord.top;

    var rect = document.getElementById(j);

    if (rect == null) {

        rect = document.createElement("div");

        rect.id = j;

        var pElement = document.getElementById("imgDiv");

        pElement.appendChild(rect);

    }

    if (w < 0) {

        w = 10;

    }

    if (h < 0) {

        h = 10;

    }

    var l = parseInt(document.getElementById("hright").value) + 150 + 'px';

    var style = rect.style;

    // style.width = w + "px";

    //style.height = h + "px";

    style.left = l;

    style.top = document.getElementById("htop").value;

    style.backgroundColor = "Transparent";

    //style.borderColor = "Blue";

    style.position = "absolute";

    style.borderStyle = "solid";

    style.borderWidth = 2 + "px";

    style.zIndex = 6000;

    document.getElementById(j).innerHTML = "<textarea name=\"comments\" style=\" border:0\" Title=\"Enter Comment\" id=\"T1\" value=\"EnterComment:\" onchange=\"GetText()\" ></textarea>";

    //document.getElementById(i).innerHTML = "<input type=\"Textarea\"...blah blah...></input>";

    return rect;

}



function GetText() {

    array1.push(document.getElementById('T1').value);

    alert(array1.join(', '));

}

</script>