CalendarExtender and getting the correct date format or change UI Culture of CalenderExtender

Change  ui culture of calendarextender or apply UI Culture on CalenderExtender of Ajax Control toolkit.

 Firstly, add Culture and UI Culture information to your web.config file.

<system.web>
    <globalization uiCulture="en" culture="en-GB" />
system.web>

Sett the EnableScriptGlobalization and EnableScriptLocalization to true as properties of the ScriptManager.

<cc1:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"
    EnablePartialRendering="true"
    EnableScriptGlobalization="true"
    EnableScriptLocalization="true">
cc1:ToolkitScriptManager>