RowFilter

I'm using RowFilter to sort a gridview when a dropdown menu selectedIndex is changed

when the page loads, the gridview displays and the dropdown menu is populated.

but, when I make a selection in the dropdown menu, the gridview comes up blank.

I've tried just hardcoding a value for the RowFilter to see if that would work and the gridview still comes up blank.

Any help is appreciated.
Thanks.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using DataViewRowFilterExample.NorthwindTableAdapters;
 
namespace DataViewRowFilterExample
{
    public partial class _Default : System.Web.UI.Page
    {
        CustomersTableAdapter custAdapter = new CustomersTableAdapter();
        CountriesTableAdapter countryAdapter = new CountriesTableAdapter();
        Northwind.CustomersDataTable custdt = new Northwind.CustomersDataTable();
        Northwind.CountriesDataTable countrydt = new Northwind.CountriesDataTable();
        Northwind ds = new Northwind();
 
        protected void Page_Load(object sender, EventArgs e)
        {
            custAdapter.Fill(custdt);
            countryAdapter.Fill(countrydt);
 
            if (!Page.IsPostBack)
            {
                ddlCountries.DataSource = countrydt;
                ddlCountries.DataValueField = "Country";
                ddlCountries.DataTextField = "Country";
                ddlCountries.DataBind();
           
                gvCustomers.DataSource = custdt;
                gvCustomers.DataBind();
            }
        }
 
        protected void ddlCountries_SelectedIndexChanged(object sender, EventArgs e)
        {
            int selectIndex = ddlCountries.SelectedIndex;
 
            DataView dv = new DataView();
            //dv.RowFilter = "Country = " + ddlCountries.SelectedItem.Value.ToString();
            dv.RowFilter = "Country = 'USA'";
            gvCustomers.DataSource = dv;
            gvCustomers.DataBind();
 
            ddlCountries.SelectedIndex = selectIndex;
        }
    }
}

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-Dman100-Software ConsultantAsked:
Who is Participating?
 
Obadiah ChristopherConnect With a Mentor Commented:
dv = custdt.DefaultView;
0
 
Bob LearnedCommented:
I would suggest a different course of action--use the DataView and the RowFilter all the time, and not just in the DropDownList_SelectedIndexChanged event handler.
0
 
Obadiah ChristopherCommented:
U missed out this sentence...

DataView dv = custdt.Tables[0].DefaultView;

The code should look like this

DataView dv = custdt.Tables[0].DefaultView;
dv.RowFilter = "Country = 'USA'";
            gvCustomers.DataSource = dv;
            gvCustomers.DataBind();
0
 
ajollyCommented:
of course..

You are just saying

DataView dv = new DataView();

which will create only empty view for you.
and you are binding with this empty view... so definitely .. you should see no records.

Probably your view should come from the datatable custdt
0
 
-Dman100-Software ConsultantAuthor Commented:
I tried the following, but the datagrid is still empty?  Is this not the correc syntax?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using DataViewRowFilterExample.NorthwindTableAdapters;
 
namespace DataViewRowFilterExample
{
    public partial class _Default : System.Web.UI.Page
    {
        CustomersTableAdapter custAdapter = new CustomersTableAdapter();
        CountriesTableAdapter countryAdapter = new CountriesTableAdapter();
        Northwind.CustomersDataTable custdt = new Northwind.CustomersDataTable();
        Northwind.CountriesDataTable countrydt = new Northwind.CountriesDataTable();
        Northwind ds = new Northwind();
 
        protected void Page_Load(object sender, EventArgs e)
        {
            custAdapter.Fill(custdt);
            countryAdapter.Fill(countrydt);
 
            if (!Page.IsPostBack)
            {
                ddlCountries.DataSource = countrydt;
                ddlCountries.DataValueField = "Country";
                ddlCountries.DataTextField = "Country";
                ddlCountries.DataBind();
           
                gvCustomers.DataSource = custdt;
                gvCustomers.DataBind();
            }
        }
 
        protected void ddlCountries_SelectedIndexChanged(object sender, EventArgs e)
        {
            int selectIndex = ddlCountries.SelectedIndex;
 
            DataView dv = new DataView();
            dv = ds.Customers.DefaultView;
            //dv.RowFilter = "Country = " + ddlCountries.SelectedItem.Value.ToString();
            dv.RowFilter = "Country = 'USA'";
            gvCustomers.DataSource = dv;
            gvCustomers.DataBind();
 
            ddlCountries.SelectedIndex = selectIndex;
        }
    }
}

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