Ajax MaskEdit For Date Validator.....

  <asp:TextBox ID="txtShipmentDate" runat="server" Width="120px" ValidationGroup="a"></asp:TextBox>    
    <asp:MaskedEditExtender ID="MaskedEditExtender1" runat="server"
        TargetControlID="txtShipmentDate"
        MaskType="Date"
        Mask="99/99/9999"
        MessageValidatorTip="true"
        CultureName="en-US"
        OnFocusCssClass="MaskedEditFocus"
        OnInvalidCssClass="MaskedEditError"
        DisplayMoney="Left"
        AcceptNegative="Left"
        ErrorTooltipEnabled="True" />
    <asp:MaskedEditValidator ID="MaskedEditValidator1" runat="server"
        ControlExtender="MaskedEditExtender1"
        ControlToValidate="txtShipmentDate"
        EmptyValueMessage="Date is required"
        InvalidValueMessage="Date is invalid"
        Display="Dynamic"
        TooltipMessage=""
        EmptyValueBlurredText="*"
        InvalidValueBlurredMessage="*" ForeColor="Red" ValidationGroup="a"/>
<br />
<asp:Button ID="submit" Text="submit" runat="server" ValidationGroup="a"/>

Property Of MaskEdit

• MaskType - Type of validation to perform:
  None - No validation
  Number - Number validation
  Date - Date validation
  Time - Time validation
  DateTime - Date and time validation
• Mask Characters and Delimiters
  9 - Only a numeric character
  L - Only a letter
  $ - Only a letter or a space
  C - Only a custom character (case sensitive)
  A - Only a letter or a custom character
  N - Only a numeric or custom character
  ? - Any character
  
  / - Date separator
  : - Time separator
  . - Decimal separator
  , - Thousand separator
  \ - Escape character
  { - Initial delimiter for repetition of masks
  } - Final delimiter for repetition of masks
  
  Examples:
  9999999 - Seven numeric characters
  99\/99 - Four numeric characters separated in the middle by a "/"
• AcceptAMPM - True to display an AM/PM symbol
• AcceptNegative - True if the negative sign (-) is allowed
  None - Do not show the negative sign
  Left - Show the negative sign on the left of the mask
  Right - Show the negative sign on the right of the mask
• AutoComplete - True to automatically fill in empty mask characters not specified by the user
  MaskType=Number - Empty mask characters will be filled with zeros
  MaskType=Time - Empty mask characters will be filled with the current time
  MaskType=Date - Empty mask characters will be filled with the current date
  MaskType=DateTime - Empty mask characters will be filled with the current date/time
• AutoCompleteValue - Default character to use when AutoComplete is enabled
• Century - Default century used when a date mask only has two digits for the year
• ClearMaskOnLostFocus - True to remove the mask when the TextBox loses focus
• ClearTextOnInvalid - True to clear the TextBox when invalid text is entered
• ClipboardEnabled- True to allow copy/paste with the clipboard
• ClipboardText - Prompt text to use when a clipboard paste is performed
• DisplayMoney - Specifies how the currency symbol is displayed
  None - Do not show the currency symbol
  Left - Show the currency symbol on the left of the mask
  Right - Show the currency symbol on the right of the mask
• ErrorTooltipCssClass - CSS class for the tooltip message
• ErrorTooltipEnabled - True to show a tooltip message when the mouse hovers over an invalid TextBox
• Filtered - Valid characters for mask type "C" (case-sensitive)
• InputDirection - Text input direction
  LeftToRight - Left to Right
  RightToLeft - Right to left
• MessageValidatorTip - Message displayed when editing in TextBox
• PromptChararacter - Prompt character for unspecified mask characters
• UserDateFormat - Custom date format
• UserTimeFormat - Custom time format
• OnFocusCssClass - CSS class used when the TextBox receives focus
• OnFocusCssNegative - CSS class used when the TextBox gets focus with a negative value
• OnBlurCssNegative - CSS class used when the TextBox loses focus with a negative value
• OnInvalidCssClass - CSS class used when the text is not valid.
• CultureName - Name of culture to use (overrides the default page culture)
• CultureAMPMPlaceholder - Culture override
• CultureCurrencySymbolPlaceholder - Culture override
• CultureDateFormat - Culture override
• CultureDatePlaceholder - Culture override
• CultureDecimalPlaceholder - Culture override
• CultureThousandsPlaceholder - Culture override
• CultureTimePlaceholder - Culture override