Using the CompareValidator control to compare user input date with today's date

Question

hey..i would like to compare the current date with the date entered by user..however, i'm encountering errors so far..

i tried something like this:

<asp:TextBox id="txtDate1" runat="server" />    
<asp:CompareValidator runat="server" ErrorMessage="The date must be greater than today"
    ControlToValidate="txtDate1" type="date" 
    ValuetoCompare="DateTime.Today.ToShortDateString()" />

and i got an error stating that the value of DateTime.Today.ToShortDateString() of the ValueToCompare property of "" cannot be converted to type 'date' i also tried ValueToCompare="DateTime.Now.Date()" and i got the same error message.

please help me and i greatly appreciate it.

Answer 1

You're just using the ValueToCompare property as a literal string. You need to use ASP tags in it if you want to execute code to get a dynamic value. Try this:

<asp:comparevalidator runat="server" 
  errormessage="The date must be greater than today"
  controltovalidate="txtDate1" type="date" 
  valuetocompare="<%# DateTime.Today.ToShortDateString() %>" />

Then in your Page_Load method, call Page.DataBind().

This will execute the databinder code when the page is loaded, and put the value in between the quotes.

Answer 2

    <asp:CompareValidator ID="CompareValidator3" runat="server" 
                        ControlToValidate="TextBox1" ErrorMessage="Date should be on or after today" 
                        Operator="GreaterThanEqual" Type="Date">
</asp:CompareValidator>

In the page load event set the validator's value to compare as

CompareValidator3.ValueToCompare = DateTime.Now.ToShortDateString();