add query items in datagrid columns

This will show you how.

http://authors.aspalliance.com/aspxtreme/webforms/controls/addingboundfieldstogridview.aspx
http://aspnet101.com/aspnet101/tutorials.aspx?id=56

However I would personally use a DataTable first , perform all the processing and then bind to a datagrid

Hi,
I already have my fields boung, what I need to do is create a dynamic column that adds the rest of the columns together.  Here is my DG, what I need to do is take the AUTH_STR column + ACN column - ASGN_STR to get a new column called VAC

<Columns>
<asp:BoundColumn DataField="UIC" HeaderText="Uic"></asp:BoundColumn>
<asp:BoundColumn DataField="City" HeaderText="City"></asp:BoundColumn>
<asp:BoundColumn DataField="Para" HeaderText="Para"></asp:BoundColumn>
<asp:BoundColumn DataField="Line" HeaderText="Line"></asp:BoundColumn>
<asp:BoundColumn DataField="Grade" HeaderText="Grade"></asp:BoundColumn>
<asp:BoundColumn DataField="DMOS" HeaderText="DMOS"></asp:BoundColumn>
<asp:BoundColumn DataField="Gender" HeaderText="Gender"></asp:BoundColumn>
<asp:BoundColumn DataField="AUTH_STR" HeaderText="Auth_Str"></asp:BoundColumn>
<asp:BoundColumn DataField="OS" HeaderText="Over_Str"></asp:BoundColumn>
<asp:BoundColumn DataField="ASGN_STR" HeaderText="Asgn_Str"></asp:BoundColumn>
<asp:BoundColumn DataField="ACN" HeaderText="ACN_ASGN"></asp:BoundColumn>
<asp:BoundColumn DataField="Unit_Type" HeaderText="Unit Type"></asp:BoundColumn>
<asp:BoundColumn DataField="Unit_Stat" HeaderText="Unit Stat"></asp:BoundColumn>
<asp:TemplateColumn HeaderText="Request">
<ItemTemplate>
<asp:Button ID="btnRequest" runat="server" Text="Request" ForeColor="blue" Width="60" CommandName="Request"></asp:Button>
</ItemTemplate>
</asp:TemplateColumn>
</Columns>

Are you trying to add/subtract values from the columns or combine them?

If you are trying to combine
Your going to have to fill a DataTable first and then bind to the DG

Here is an example.

dt.Columns.Add(new DataColumn("VAC",
System.Type.GetType("System.String"), "[AUTH_STR] [ACN]"));

Select allOpen in new window

Hi, here is what i tried but I get a blue underline under New datacolumn to the end

value of type system.data.datacolumn cannot be converted to system.web.ui.webcontrols.datacolumn


SQl = "Select * from tables"

myDataTable = New DataTable
myDataTable = getData(sql)

 myDataGrid.Columns.Add(New DataColumn("VAC2", System.Type.GetType("system.string"), "[AUTH_STR] + [ACN] - [ASGN_STR]"))

myDataGrid.DataSource = myDataTable
 myDataGrid.DataBind()

myDataGrid.Columns.Add should be myDataTable.Columns.Add

Ok changed, but i get the following error. which point tot he new line.  I tried putting it after databind and in middle and before, then i tired this. but still got the error below.

 myDataTable.Columns.Add(New DataColumn("VAC2", System.Type.GetType("system.string"), "[myDataTable.Rows(0)(7)] + [myDataTable.Rows(0)(8)] - [myDataTable.Rows(0)(9)]"))

Error
'dataType' argument cannot be null. Parameter name: dataType
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentNullException: 'dataType' argument cannot be null. Parameter name: dataType

Are the values in the rows strings or integers?

They should be all integers, because I can add them in my sql code. but then it takes to long.

try changing ("system.string") to ("system.integer")

Hi,
get he same error as before no matter if its.

 myDataTable = New DataTable
myDataTable = getData(sql)

myDataTable.Columns.Add(New DataColumn("VAC2", System.Type.GetType("system.integer"), "[myDataTable.Rows(0)(7)] + [myDataTable.Rows(0)(8)] - [myDataTable.Rows(0)(9)]"))

 myDataGrid.DataSource = myDataTable
myDataGrid.DataBind()

or

myDataTable = New DataTable
myDataTable = getData(sql)

myDataTable.Columns.Add(New DataColumn("VAC2", System.Type.GetType("system.integer"), "[AUTH_STR] + [ACN] - [ASGN_STR]"))

myDataGrid.DataSource = myDataTable
myDataGrid.DataBind()

HI,
I tired this from anthoer web site but get a totally different error.

 myDataTable.Columns.Add("VAR2", myDataTable.Rows(0)(7))

Here is how they have for DataGridView instead of asp.net 1.1 datagrid
'---adding columns---
        DataGridView1.Columns.Add("ID", "Product ID")
        DataGridView1.Columns.Add("Name", "Product Name")

But the error I get is the follwoing
Specified cast is not valid.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Specified cast is not valid.

Closing out old questions, works