unable to access data assigned you a usercontrol uing web ct

Question

Hi,

 

I have assigned data to a usercontrol using below code.

function calendarPickerCSD(stat)

{

//alert(stat);

var ret=window.showModalDialog('PopupCal.aspx?ShowDate='+ document.getElementById('Usrdate_txtSignDate').value+ '','calendarPopup',stat);

if (ret!=null)

{

document.getElementById('UsrSite_txtSignDate'').innerText=ret

;

alert("Sign Date can not be changed after the page gets saved.");

}

}

 

But, on vb page when I am trying to access the same text using txtSignDate.text, it is returning null.

 

We are migrating from 1.1 framework to 4.0. Team, please suggest on this.