Try this:
protected void RadGrid1_ItemCommand(object sender, GridCommandEventArgs e)
{
if (e.CommandName == "btnRelease")
{
GridDataItem item = (GridDataItem)e.Item;
// Replace "TrxId" with the reference to the item containing your TrxId
string TrxId = item["TrxId"].Text;
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["ZEUS"].ConnectionString);
con.Open();
SqlCommand command = new SqlCommand("UPDATE [TransactsData] SET [IsReleased] = 1, [TimeReleased] = GETDATE() WHERE [TrxId] = @TrxId", con);
command.Parameters.AddWithValue("@TrxId", TrxId);
command.ExecuteNonQuery();
con.Close();
}
}
Btw: I am supposing you have something like this in your RadGrid:
<telerik:GridBoundColumn DataField="TrxId" HeaderText="Transaction ID" UniqueName="TrxId">