Rahul's space

Add link like following which redirect to popup page that you want to open on button click using fancybox

[1] <a href=”../Scripts/ValidationMessage.aspx” class=”fancybox fancybox.iframe” id=”hiddenlink_confirm” />

Add following js function on head of page along with fancybox script

[2] <script type=”text/javascript”>

function OpenValidationMessagePopup() {
var alink = document.getElementById(“hiddenlink_confirm”);
alink.click();
}

[3] Write following code on button click event

Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSave.Click

Dim sb As New StringBuilder()

sb.AppendFormat(“OpenValidationMessagePopup();”)
ScriptManager.RegisterStartupScript(Me.Page, Me.[GetType](), “OpenValidationMessagePopup” + DateAndTime.Now, sb.ToString(), True)

End Sub

Will add some more information to the above steps, hope this help !