Apply Filter on Child Data Grid

[dorandoran]

I have a applyfilter that works with another page (using this sample http://www.c-sharpcorner.com/Blogs/B...spx?BlogId=825). can similar be implemented with following datasource (following datasource is for child gridview). I have a label where user will input a value for filter. i like to take that value and implement it with the code i posted so that the childgrid now have filtered data. hope it makes sense. (see example here: http://www.codeproject.com/KB/aspnet...dGridView.aspx ) please suggest.

private DataTable ChildDataSource(string strlpID, string strSort)
{
SqlConnection conn;
SqlDataAdapter daProducts;
DataTable dsProducts;
string strQRY = "";
conn = new SqlConnection(@"Server=riverstone; Integrated Security=SSPI; Database=nw");
strQRY = "SELECT [Orders].[CustomerID],[Orders].[OrderID]," +
 "[Orders].[ShipAddress],[Orders].[Freight],[Orders].[ShipName] FROM [Orders]" +
 " WHERE [Orders].[CustomerID] = '" + strlpID + "'" +
 "UNION ALL " +
 "SELECT '" + strlpID + "','','','','' FROM [Orders] WHERE [Orders].[CustomerID] = '" + strlpID + "'" +
 "HAVING COUNT(*)=0 " + strSort;
daProducts = new SqlDataAdapter(strQRY, conn);
dsProducts = new DataTable();
daProducts.Fill(dsProducts);
return dsProducts;
}

[dorandoran]

I added parameters and it's seems to be working. however, it breaks when I dont pick anything from the dropdown filter box. my drop down has 30,60 and 90 and "" which is filtered against quantity. so i get "input string was not a correct format" error when i dont select anything from the drop down. I want the parameter to be optional. for example, show all the records when nothing is picked from the dropdown. (filter part is working).