I have a dynamic calendar extender & dynamic textbox being generated and an image button to show the calendar extender. I've extended the textbox to add an OnClick event, but I wanted to know how I could show a calendar extender on the server side if possible. Thanks.

What I get from your post is that you want to add a  CalendarExtended to a dynamic textbox.  

TextBox txtDateWorkedOn = new TextBox();
txtDateWorkedOn.Text = DateTime.Now.ToShortDateString();
txtDateWorkedOn.ID = "txtDateWorkedOn_" + idNumber.ToString();
ImageButton calendarImage = new ImageButton();
calendarImage.CssClass = "imagebutton";
calendarImage.ImageUrl = "images/icon-calendar.gif";
calendarImage.ID = "calendarImage_" + idNumber.ToString();
AjaxControlToolkit.CalendarExtender calendarExtender = new AjaxControlToolkit.CalendarExtender();
calendarExtender.TargetControlID = txtDateWorkedOn.ID;
calendarExtender.PopupButtonID = calendarImage.ID;

What are you exactly trying to do? CalendarExtended will be displayed wherever the application is viewed in browser, even on the server.

I already have it setup to display the control on image click via popupbuttonid. The question is I have setup a textbox with a server side OnClick event and how would I display or render the calendar control onclick?

Do you really need an OnClick event to do that?

Whether or not I need an onclick event or not is irrelevant.... I'm asking a simple question that needs a simple answer. 

Is this possible either client or server side. IE: on server side calextender.show() or textbox.attributes.add("onclick","showcalendar()")

Heres a simple answer. Yes you can. 

function ShowCalendar() {
    $find('<%=CalendarExtender1.ClientID %>').show();
}

TextBox1.Attributes.Add("onclick", "javascript:return ShowCalendar();");

Thanks, that helps. Now I could probably pass the id to the func and it'll work more dynamically.

For some reason the TargetControlID property doesn't come up for me when I declare the calendar extender.

Checking the object browser it shows the property buried underneath "Base Types\Extender Control Base" but I can't just use it like you did above:

calendarExtender.TargetControlID = txtDateWorkedOn.ID;

Any ideas??

dtabraha:

For some reason the TargetControlID property doesn't come up for me when I declare the calendar extender.

Checking the object browser it shows the property buried underneath "Base Types\Extender Control Base" but I can't just use it like you did above:

calendarExtender.TargetControlID = txtDateWorkedOn.ID;

Any ideas??

Just add reference to System.Web.Extensions and everything will be fine.