Demonstrates the RequiredSelectionValidator

<script runat="server">

   protected void Page_Load(object sender, EventArgs e)
   {
      TimePicker1.Items.AddTimes(new TimeSpan(9, 0, 0), new TimeSpan(18, 0, 0), 60);
      TimePicker1.Items.Add(new PeterBlum.DES.Web.WebControls.SpecialTimeNoValue("None"));
      
      // Load sample data only once, when the page is first loaded.
      if (!IsPostBack)
      {
         DataList1.DataSource = CreateDataSource();
         DataList1.DataBind();
      }
   }
   protected ICollection CreateDataSource()
   {
      // Create sample data for the DataList control.
      DataTable dt = new DataTable();
      DataRow dr;
      // Define the columns of the table.
      dt.Columns.Add(new DataColumn("Item", typeof(Int32)));
      dt.Columns.Add(new DataColumn("Qty", typeof(Int32)));
      dt.Columns.Add(new DataColumn("Price", typeof(double)));
      // Populate the table with sample values.
      for (int i = 0; i < 9; i++)
      {
         dr = dt.NewRow();
         dr[0] = i;
         dr[1] = i * 2;
         dr[2] = 1.23 * (i + 1);
         dt.Rows.Add(dr);
      }
      DataView dv = new DataView(dt);
      return dv;
   }
   protected void Item_Command(Object sender, DataListCommandEventArgs e)
   {
      // Set the SelectedIndex property to select an item in the DataList.
      DataList1.SelectedIndex = e.Item.ItemIndex;
      // Rebind the data source to the DataList to refresh the control.
      DataList1.DataSource = CreateDataSource();
      DataList1.DataBind();
   }
   protected void Button1_Click(object sender, EventArgs e)
   {
      if (PeterBlum.DES.Globals.WebFormDirector.IsValid)
      {
         // save your data here
      }
   }
   protected void Button2_Click(object sender, EventArgs e)
   {
      PeterBlum.DES.Globals.WebFormDirector.Validate();
      if (PeterBlum.DES.Globals.WebFormDirector.IsValid)
      {
         // save your data here
      }
   }
   
</script>

Start by clicking Submit to see existing errors. Notice that the last example of a DataList
does not report an error because it only uses server side validation.<br/>
<des:Button ID="Button3" runat="server" Text="Submit" OnClick="Button1_Click"></des:Button>
<br/>
<h2>DES Calendar</h2>
<des:Calendar ID="Calendar1" runat="server">
   <ClearCommand ShowField="RecommendedRow" />
</des:Calendar>
<des:RequiredSelectionValidator ID="RSV1" runat="server" 
   ControlIDToEvaluate="Calendar1"
   ErrorMessage="Required"  />
<br/>
<br/>
<h2>TimePicker</h2>
<des:TimePicker ID="TimePicker1" runat="server" >
</des:TimePicker>
<des:RequiredSelectionValidator ID="RequiredSelectionValidator1" runat="server" 
   ControlIDToEvaluate="TimePicker1"
   ErrorMessage="Required" />
<br/>
<br/>
<h2>MonthYearPicker</h2>
<des:MonthYearPicker ID="MonthYearPicker1" runat="server" Format="FewYears">
</des:MonthYearPicker>
<des:RequiredSelectionValidator ID="RequiredSelectionValidator2" runat="server" 
   ControlIDToEvaluate="MonthYearPicker1"
   ErrorMessage="Required" ShowRequiredFieldMarker="true" />
<br/>
<br/>
<h2>MultiSelectionCalendar</h2>
<des:MultiSelectionCalendar ID="MultipleSelectionCalendar1" runat="server">
</des:MultiSelectionCalendar>
<des:RequiredSelectionValidator ID="RequiredSelectionValidator4" runat="server" 
   ControlIDToEvaluate="MultipleSelectionCalendar1"
   ErrorMessage="Required" />
<br/>
<br/>
<h2>DataList</h2>
Requires server side validation. Use the "Submit Server side validation only" to see the error. Then click a Select button
to remove the error.<br/>
<asp:DataList ID="DataList1" runat="server"  DataKeyField="Item"
   GridLines="Both" CellPadding="3" CellSpacing="0" OnItemCommand="Item_Command" >
   <HeaderStyle BackColor="#aaaadd" />
   <AlternatingItemStyle BackColor="Gainsboro" />
   <SelectedItemStyle BackColor="Yellow" />
   <HeaderTemplate>
      Items
   </HeaderTemplate>
   <ItemTemplate>
      <asp:LinkButton ID="SelectButton" Text="Select" CommandName="Select" runat="server" />
      Item <%# DataBinder.Eval(Container.DataItem, "Item")%>
   </ItemTemplate>
   <SelectedItemTemplate>
      Item: <asp:Label ID="ItemLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Item")%>'
         runat="server" />
      <br/>
      Quantity: <asp:Label ID="QtyLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Qty")%>'
         runat="server" />
      <br/>
      Price: <asp:Label ID="PriceLabel" Text='<%# DataBinder.Eval(Container.DataItem, "Price", "{0:c}")%>'
         runat="server" />
   </SelectedItemTemplate>
</asp:DataList>
<des:RequiredSelectionValidator ID="RequiredSelectionValidator5" runat="server" 
   ControlIDToEvaluate="DataList1"
   ErrorMessage="Required" />
<br/><br/>
<des:Button ID="Button1" runat="server" Text="Submit" OnClick="Button1_Click"></des:Button>
<des:Button ID="Button2" runat="server" Text="Submit Server side validation only" OnClick="Button2_Click" CausesValidation="false"></des:Button>