CheckBox Visible

phuc2583 · April 8th, 2010, 05:54 AM

Hello all

There are some error somewhere that i do not know where are
when i run the paage it is occur an error like this "Expression expected."

<asp:CheckBox Visible='<%# IIF (DataBinder.Eval(Container.DataItem,"TriplePrice") == dbnull.value,"",IIF (DataBinder.Eval(Container.DataItem,"TriplePrice") ="0",IIF (DataBinder.Eval(Container.DataItem,"TriplePrice") <>"0", DataBinder.Eval(Container.DataItem,"TriplePrice")) %>' ID="CheckBox1" runat="server" Font-Bold="False" ForeColor="#000040" Text='<%# Bind("TriplePrice") %>' />

Thanks in advance
Phuc

dparsons · April 9th, 2010, 11:24 AM

Hmmm. A couple of things:

Since you are using the IIF statement this tells me that you are using VB since there is no IIF in C#. However you are using the C# equality operator '==' which is incorrect; you should simply use '=' or 'Is' as I have done below. Next it appears that you are overcomplicating things with your IIF. Something like this should suffice: <%# IIf(Eval("TriplePrice") Is DbNull.Value, "false","true") %> So if the the value TriplePrice is null the checkbox will not be visible otherwise it will.

Honestly .aspx pages are for markup and UI elements, not conditional logic. I would definately handle this determination of visiblity on the server side in the ItemDataBound event (or similar event) of whatever control this checkbox resides in. An example of th is would be:

vb Code:

Protected Sub rpt_ItemDataBound(ByVal sender As Object, ByVal e As RepeaterItemEventArgs)
If e.Item.ItemType = ListItemType.AlternatingItem OrElse e.Item.ItemType = ListItemType.Item Then
 
     Dim obj as Object = DirectCast(e.Item.DataItem, Object)
     Dim chk as CheckBox = DirectCast(e.Item.FindControl("CheckBox1"), Literal)
 
     If obj IsNot Nothing Then
          If obj.TripleValue IsNot Nothing Then 
             chk.Visible = True
             chk.Text = Convert.ToString(obj.TripleValue)
          End If
     End If
 
End If
End Sub

Then define your CheckBox on the UI side as:

asp Code:

<asp:CheckBox Visible="False" ID="CheckBox1" runat="server" Font-Bold="False" ForeColor="#000040"  />

hth
Doug

phuc2583 · April 12th, 2010, 06:05 AM

Hey dparsons

Thanks for helping me to do it,your code is very helpful.
But i have wrote it in datagrid view, there is no item "ItemDataBound" in it
Thanks & Best Regards
Phuc Hoang

dparsons · April 12th, 2010, 07:37 AM

The GridView or the DataGridView? While it is certainly possible to host a WinForm control (which is what the DataGridView is) in an ASPX page, I have to ask the question as to why you are using that control as opposed to a GridView or a DataGrid?

Further the DataGridView does NOT have a similar event to ItemDataBound AFAIK. If you are deadst on using the DataGridView you are going to have to proceed with the IIF statements I suppose. The IIF I posted in my original response should work.

hth.
-Doug

phuc2583 · April 12th, 2010, 11:30 PM

Hello dparsons

Thanks for useful information
It work fine

Thanks & Best Regards
Phuc Hoang