ModalPopupExtender closes on any Button Click

I agree with sudesh.
You need to call .show method of modal popup extender on the raised event.

Thanks
Mahesh

Ajax modal popup closes if any controls present on it causes a postback.

use OKControlID and CancelControlID properties of the modal popup and assign your OK and cancel button ID's for these properties respectively.

If you want to perform any operations on OK and cancel, use OnOKScript and OnCancelScript properties. the scripts can be defined as javascript functions.

If you want intentional postback from the control present on popup then, after performing your postback action add a line at the end to show the popup back again
ex: mpe.Show();

It might be helpful,

Using ModalPopupExtender from AJAX Control Toolkit C#[^]

Create a Modal Popup using the Modal Popup[^]

ModalPopup as an AJAX Progress Indicator[^]

:)

protected void btnShowModal_Click(object sender, EventArgs e)
       {
          //this is the button that is used to invoke
          //Manually show the modal popup
            ModalPopupExtender1.Show();
        }

take update pannel in your form.. to avoid post back

if your model popup extender close any button click then we have the best solution show your popup also on that button in which you do not want close the popup it's prefect solution.

Laxman negi

HI
Here is my modalpopup

When I click the button "btnOk" inside my panel, then the popup disappears.

<ajaxToolkit:ModalPopupExtender ID="ModalPopupTextBoxEmpty" runat="server"
          TargetControlID="Image6"  PopupControlID="PNLTextBoxEmpty" BackgroundCssClass="modalBackground" OkControlID="btnOk"
            DropShadow="false" />