> I want to make sure that the SelectedDate property of the Calendar
> control is later than the current date or that a certain checkbox is
> selected. I tried to use a CustomValidator control with the following
> code:
>
> Private Sub validTimeFrame_ServerValidate(ByVal source As
> System.Object, ByVal args As
> System.Web.UI.WebControls.ServerValidateEventArgs) Handles
> validTimeFrame.ServerValidate
>
> If chkUnknown.Checked OrElse calTimeFrame.SelectedDate >= Date.Today
> Then
>
> args.IsValid = True
>
> Else
>
> args.IsValid = False
>
> End If
>
> End Sub
>
> As you can see, I check to see if chkUnknown is checked or if
> calTimeFrame.SelectedDate>= Date.Today. If either one is true, then I
> assign True to the IsValid property, otherwise I assign it a value of
> false. However, when I test the page it brings up the following error:
>
> [HttpException (0x80004005): Control 'calTimeFrame' referenced by the
> ControlToValidate property of 'validTimeFrame' cannot be validated.]
>
> System.Web.UI.WebControls.BaseValidator.CheckControlValidationProperty
> (String
> name, String propertyName)
> System.Web.UI.WebControls.CustomValidator.ControlPropertiesValid()
> System.Web.UI.WebControls.BaseValidator.get_PropertiesValid()
> System.Web.UI.WebControls.BaseValidator.Render(HtmlTextWriter
> writer)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
> System.Web.UI.Control.Render(HtmlTextWriter writer)
> System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter
> writer)
> System.Web.UI.WebControls.TableCell.RenderContents(HtmlTextWriter
> writer)
> System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
> System.Web.UI.Control.Render(HtmlTextWriter writer)
> System.Web.UI.WebControls.WebControl.RenderContents(HtmlTextWriter
> writer)
> System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.WebControls.Table.RenderContents(HtmlTextWriter
> writer)
> System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
> System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter
> writer)
>
> System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter
> writer)
> System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.Control.RenderChildren(HtmlTextWriter writer)
> System.Web.UI.Control.Render(HtmlTextWriter writer)
> System.Web.UI.Control.RenderControl(HtmlTextWriter writer)
> System.Web.UI.Page.ProcessRequestMain()
> Because this tells me nothing more than that the control cannot be
> validated, I do not know where to start. Any ideas? Thanks.
>