Not getting data from Datatable

Lex

Hi All, I'm using a gridview where I can select multiple lines, I store the keynames of each line into a DataTable, but having trouble using the DataTable when it comes to activating the selected products.
Here is my code to add items to the DataTable:

 

if (Session["tblSelected"] == null)
{
DataColumn actID = new DataColumn("actID");
actID.DataType = Type.GetType("System.Int32");
tblSelected.Columns.Add(actID);
DataColumn actStatus = new DataColumn("actStatus");
actStatus.DataType = Type.GetType("System.Int32");
tblSelected.Columns.Add(actStatus);
DataColumn prodCode = new DataColumn("prodCode");
prodCode.DataType = Type.GetType("System.Int32");
tblSelected.Columns.Add(prodCode);
DataColumn[] pCol = new DataColumn[1];
pCol[0] = actID;
tblSelected.PrimaryKey = pCol;
}
else
{
tblSelected = (DataTable)Session["tblSelected"];
Session["tblSelected"] = null;
}
DataRow dRow = tblSelected.NewRow();
dRow["actID"] = activationID;
dRow["actStatus"] = activationStatus;
dRow["prodCode"] = productCode;
if (!tblSelected.Rows.Contains(activationID))
{
tblSelected.Rows.Add(dRow);
}
else
{
tblSelected.Rows.Find(activationID).Delete();
}
Session["tblSelected"] = tblSelected;

I have defined my DataTable on the top

 

DataTable tblSelected = new DataTable();

My button has the following code to look through the table:

 

foreach (DataRow row in tblSelected.Rows)
{
   // My code that activates the products....   
}

Now the problem comes when I go into the foreach loop, it tels me that there are no items in tblSelected.
Anyone has any idea why after I selected a couple of rows, and confirmed they are added to the Datatable that they are not accessable from the button control?

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sam Hobbs16y ago
It is likely that use of try/catch will eliminate a few embarrassing situations such as this.
0
Lex16y ago
I first thought it was the position of where I was defining the table. But a friend of my pointed me in the right direction.
I forgot that I added the table to a session, therefore I was unable to get data from that table, as soon as I pointed the tblSelected to the session it was working.
tblSelected = (DataTable)Session["tblSelected"];
was needed before I checked every entry in the table, when I click the button. A simple mistake which is easy to read over, and even with the debugger hard to spot.

0
Sam Hobbs16y ago
Be sure to use try/catch so you don't miss something critical. If that does not determine the problem, then use the debugger to single-step through the code and ensure that everything is working as you expect.
0
Blocked Account16y ago
HI Lex,
Check the position of this line DataTable tblSelected = new DataTable();
i think this line will be in page load, when you click on button it again create the new instance of datatable and all old data get remove.
put it inside the !Page.IsPostBack under Page Load.
and it would be better if you post complete code for understand the problem better.
Thanks
0