Public Enum ContextMenuType 
   Inherits System.Enum

Dim instance As ContextMenuType

public enum ContextMenuType : System.Enum 

//Markup code
<ContextMenus> 
        <FarPoint:ContextMenu Type="Viewport"> 
          <Items> 
            <FarPoint:MenuItem Enabled="True" ImageUrl="http://linktoimagehere/abc.jpc" Text="Menu item 1"> 
                <ItemTemplate> 
                <asp:TextBox ID="bac" runat="server" /> 
                </ItemTemplate> 
            </FarPoint:MenuItem> 
            <FarPoint:MenuItem Text="Sort" ImageUrl="http://linktoimagehere/abc.jpc"> 
                <ChildItems >                  
                  <FarPoint:MenuItem  Text="Child Item1"  ImageUrl="http://avc/abc.jpc"></FarPoint:MenuItem> 
                  <FarPoint:MenuItem Text="Child Item2"></FarPoint:MenuItem> 
                </ChildItems> 
            </FarPoint:MenuItem> 
            <FarPoint:MenuItem Enabled="True" ImageUrl="http://linktoimagehere/abc.jpc">Menu item 3</FarPoint:MenuItem> 
          </Items> 
        </FarPoint:ContextMenu> 
      </ContextMenus> 

protected void Page_Load(object sender, System.EventArgs e)
{
if (this.IsPostBack) return;
FpSpread1.EnableContextMenu = true;
//Create this viewport menu using markup or the ContextMenus property in the property window
FarPoint.Web.Spread.ContextMenu viewportMenu = FpSpread1.ContextMenus[FarPoint.Web.Spread.ContextMenuType.Viewport];
FarPoint.Web.Spread.MenuItem customViewportItem = new FarPoint.Web.Spread.MenuItem("Viewport item 1");
customViewportItem.ChildItems.Add(new FarPoint.Web.Spread.MenuItem("Child item 1"));
customViewportItem.ChildItems.Add(new FarPoint.Web.Spread.MenuItem("Child item 2"));
viewportMenu.Items.Add(customViewportItem);

//This row header menu is created here (no markup or design properties) 
FarPoint.Web.Spread.ContextMenu rowHeaderContextMenu = new FarPoint.Web.Spread.ContextMenu();
rowHeaderContextMenu.Type = FarPoint.Web.Spread.ContextMenuType.RowHeader;
FarPoint.Web.Spread.MenuItem rowHeaderItem = new FarPoint.Web.Spread.MenuItem("RowHeader item 1");
rowHeaderItem.ChildItems.Add(new FarPoint.Web.Spread.MenuItem("Child item 1"));
rowHeaderItem.ChildItems.Add(new FarPoint.Web.Spread.MenuItem("Child item 2"));
rowHeaderContextMenu.Items.Add(rowHeaderItem);
FpSpread1.ContextMenus.Add(rowHeaderContextMenu); 
}

//Markup code
<ContextMenus> 
        <FarPoint:ContextMenu Type="Viewport"> 
          <Items> 
            <FarPoint:MenuItem Enabled="True" ImageUrl="http://linktoimagehere/abc.jpc" Text="Menu item 1"> 
                <ItemTemplate> 
                <asp:TextBox ID="bac" runat="server" /> 
                </ItemTemplate> 
            </FarPoint:MenuItem> 
            <FarPoint:MenuItem Text="Sort" ImageUrl="http://linktoimagehere/abc.jpc"> 
                <ChildItems >                  
                  <FarPoint:MenuItem  Text="Child Item1"  ImageUrl="http://avc/abc.jpc"></FarPoint:MenuItem> 
                  <FarPoint:MenuItem Text="Child Item2"></FarPoint:MenuItem> 
                </ChildItems> 
            </FarPoint:MenuItem> 
            <FarPoint:MenuItem Enabled="True" ImageUrl="http://linktoimagehere/abc.jpc">Menu item 3</FarPoint:MenuItem> 
          </Items> 
        </FarPoint:ContextMenu> 
      </ContextMenus> 

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If (IsPostBack) Then
    Return
End If
FpSpread1.EnableContextMenu = True
'Create this viewport menu using markup or the ContextMenus property in the property window
Dim viewportMenu As FarPoint.Web.Spread.ContextMenu = FpSpread1.ContextMenus(FarPoint.Web.Spread.ContextMenuType.Viewport)
Dim customViewportItem As New FarPoint.Web.Spread.MenuItem("Viewport item 1")
customViewportItem.ChildItems.Add(New FarPoint.Web.Spread.MenuItem("Child item 1"))
customViewportItem.ChildItems.Add(New FarPoint.Web.Spread.MenuItem("Child item 2"))
viewportMenu.Items.Add(customViewportItem)

'This row header menu is created here (no markup or design properties)  
Dim rowHeaderContextMenu As New FarPoint.Web.Spread.ContextMenu()
rowHeaderContextMenu.Type = FarPoint.Web.Spread.ContextMenuType.RowHeader
Dim rowHeaderItem As New FarPoint.Web.Spread.MenuItem("RowHeader item 1")
rowHeaderItem.ChildItems.Add(New FarPoint.Web.Spread.MenuItem("Child item 1"))
rowHeaderItem.ChildItems.Add(New FarPoint.Web.Spread.MenuItem("Child item 2"))
rowHeaderContextMenu.Items.Add(rowHeaderItem)
FpSpread1.ContextMenus.Add(rowHeaderContextMenu)
End Sub