It will be a lot easier if you use the calendar control to lessen the typo error or format issues. Anyway you can try this:
<asp:Calendar ID="calFrom" runat="server" OnSelectionChanged="calFrom_SelectionChanged" OnDayRender="calDataBind" />
<asp:TextBox ID="txtFrom" runat="server" />
<br />
<asp:Calendar ID="calTo" runat="server" OnSelectionChanged="calTo_SelectionChanged" OnDayRender="calDataBind" />
<asp:TextBox ID="txtTo" runat="server" />
<br />
<asp:CompareValidator ID="CompareValidator1" runat="server" ControlToCompare="txtFrom" ControlToValidate="txtTo" ErrorMessage="Date from should be earlier than date to" Operator="GreaterThan" />
<br />
<asp:Button ID="btnValidate" runat="server" Text="Validate!" />
Code behind:
protected void calFrom_SelectionChanged(object sender, EventArgs e)
{
txtFrom.Text = calFrom.SelectedDate.ToShortDateString();
}
protected void calTo_SelectionChanged(object sender, EventArgs e)
{
txtTo.Text = calTo.SelectedDate.ToShortDateString();
}
protected void calDataBind(object sender, DayRenderEventArgs e)
{
if (e.Day.Date > DateTime.Now)
{
e.Day.IsSelectable = false;
}
}
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