Bind GridView on RadioButtonList selection in ASP.Net

Hi aruneddy,

Please take reference to the below code and correct your code.

HTML

<asp:RadioButtonList ID="rbllist" runat="server" OnSelectedIndexChanged="rbllist_SelectedIndexChanged"
    AutoPostBack="true">
    <asp:ListItem Text="Country" Value="Country"></asp:ListItem>
    <asp:ListItem Text="City" Value="City"></asp:ListItem>
</asp:RadioButtonList>
<asp:DropDownList runat="server" ID="ddlCities">
    <asp:ListItem Text="Seattle" />
    <asp:ListItem Text="Tacoma" />
    <asp:ListItem Text="Kirkland" />
    <asp:ListItem Text="Redmond" />
    <asp:ListItem Text="London" />
</asp:DropDownList>
<asp:GridView ID="GridView1" runat="server" Height="200px" Width="725px" AutoGenerateColumns="False"
    AllowPaging="True" CellPadding="0" PageSize="10" BackColor="White" BorderColor="#3366CC"
    BorderStyle="None" BorderWidth="1px">
    <Columns>
        <asp:TemplateField>
            <ItemTemplate>
                <asp:Label ID="lblcounty" runat="server"></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="">
            <ItemTemplate>
                <asp:CheckBox ID="CheckBox1" Style="padding: 2px 10px; margin-left: 30px; width: 50px;
                    height: 50px;" runat="server" />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
    <EmptyDataTemplate>
        <div align="center">
            No records found.</div>
    </EmptyDataTemplate>
    <FooterStyle BackColor="#99CCCC" ForeColor="#003399" Height="30px" />
    <HeaderStyle BackColor="#003399" Font-Bold="True" ForeColor="#CCCCFF" Height="30px" />
    <PagerStyle BackColor="#99CCCC" ForeColor="#003399" HorizontalAlign="left" />
    <RowStyle BackColor="White" ForeColor="#003399" Height="30px" />
    <SelectedRowStyle BackColor="#009999" Font-Bold="True" ForeColor="#CCFF99" />
    <SortedAscendingCellStyle BackColor="#EDF6F6" />
    <SortedAscendingHeaderStyle BackColor="#0D4AC4" />
    <SortedDescendingCellStyle BackColor="#D6DFDF" />
    <SortedDescendingHeaderStyle BackColor="#002876" />
</asp:GridView>

Namespaces

C#

using System.Data;
using System.Data.SqlClient;
using System.Configuration;

VB.Net

Imports System.Data.SqlClient
Imports System.Data

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindGrid();
    }
}

private void BindGrid()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT Country FROM Employees", con))
        {
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataTable dt = new DataTable();
            da.Fill(dt);
            GridView1.Columns[0].HeaderText = "Available counties";
            GridView1.Columns[0].HeaderStyle.ForeColor = System.Drawing.Color.White;
            GridView1.DataSource = dt;
            GridView1.DataBind();
            if (dt.Rows.Count > 0)
            {
                for (int j = 0; j < GridView1.Rows.Count; j++)
                {
                    Label lblname = GridView1.Rows[j].FindControl("lblcounty") as Label;
                    lblname.Text = dt.Rows[j]["Country"].ToString();
                }
            }
        }
    }
}

protected void rbllist_SelectedIndexChanged(object sender, EventArgs e)
{
    if (rbllist.SelectedItem.Text == "Country")
    {
        string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand("SELECT DISTINCT Country FROM Employees WHERE City=@City", con))
            {
                cmd.Parameters.AddWithValue("@City", ddlCities.SelectedItem.Text);
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);
                GridView1.Columns[0].HeaderText = "Available counties";
                GridView1.Columns[0].HeaderStyle.ForeColor = System.Drawing.Color.White;
                GridView1.DataSource = dt;
                GridView1.DataBind();
                if (dt.Rows.Count > 0)
                {
                    int i = 0;
                    foreach (GridViewRow row in GridView1.Rows)
                    {
                        Label lblname = row.FindControl("lblcounty") as Label;
                        lblname.Text = dt.Rows[i]["Country"].ToString();
                        i++;
                    }
                }
            }
        }
    }
    else if (rbllist.SelectedItem.Text == "City")
    {
        string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand("SELECT DISTINCT Title FROM Employees WHERE City=@City", con))
            {
                cmd.Parameters.AddWithValue("@City", ddlCities.SelectedItem.Text);
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                da.Fill(dt);
                GridView1.Columns[0].HeaderText = "Available Titles";
                GridView1.Columns[0].HeaderStyle.ForeColor = System.Drawing.Color.White;
                GridView1.DataSource = dt;
                GridView1.DataBind();
                if (dt.Rows.Count > 0)
                {
                    int i = 0;
                    foreach (GridViewRow row in GridView1.Rows)
                    {
                        Label lblname = row.FindControl("lblcounty") as Label;
                        lblname.Text = dt.Rows[i]["Title"].ToString();
                        i++;
                    }
                }
            }
        }
    }
    else
    {
        this.BindGrid();
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindGrid()
    End If
End Sub

Private Sub BindGrid()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT Country FROM Employees", con)
            Dim da As SqlDataAdapter = New SqlDataAdapter(cmd)
            Dim dt As DataTable = New DataTable()
            da.Fill(dt)
            GridView1.Columns(0).HeaderText = "Available counties"
            GridView1.Columns(0).HeaderStyle.ForeColor = System.Drawing.Color.White
            GridView1.DataSource = dt
            GridView1.DataBind()

            If dt.Rows.Count > 0 Then

                For j As Integer = 0 To GridView1.Rows.Count - 1
                    Dim lblname As Label = TryCast(GridView1.Rows(j).FindControl("lblcounty"), Label)
                    lblname.Text = dt.Rows(j)("Country").ToString()
                Next
            End If
        End Using
    End Using
End Sub

Protected Sub rbllist_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
    If rbllist.SelectedItem.Text = "Country" Then
        Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
        Using con As SqlConnection = New SqlConnection(constr)
            Using cmd As SqlCommand = New SqlCommand("SELECT DISTINCT Country FROM Employees WHERE City=@City", con)
                cmd.Parameters.AddWithValue("@City", ddlCities.SelectedItem.Text)
                Dim da As SqlDataAdapter = New SqlDataAdapter(cmd)
                Dim dt As DataTable = New DataTable()
                da.Fill(dt)
                GridView1.Columns(0).HeaderText = "Available counties"
                GridView1.Columns(0).HeaderStyle.ForeColor = System.Drawing.Color.White
                GridView1.DataSource = dt
                GridView1.DataBind()

                If dt.Rows.Count > 0 Then
                    Dim i As Integer = 0

                    For Each row As GridViewRow In GridView1.Rows
                        Dim lblname As Label = TryCast(row.FindControl("lblcounty"), Label)
                        lblname.Text = dt.Rows(i)("Country").ToString()
                        i += 1
                    Next
                End If
            End Using
        End Using
    ElseIf rbllist.SelectedItem.Text = "City" Then
        Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
        Using con As SqlConnection = New SqlConnection(constr)
            Using cmd As SqlCommand = New SqlCommand("SELECT DISTINCT Title FROM Employees WHERE City=@City", con)
                cmd.Parameters.AddWithValue("@City", ddlCities.SelectedItem.Text)
                Dim da As SqlDataAdapter = New SqlDataAdapter(cmd)
                Dim dt As DataTable = New DataTable()
                da.Fill(dt)
                GridView1.Columns(0).HeaderText = "Available Titles"
                GridView1.Columns(0).HeaderStyle.ForeColor = System.Drawing.Color.White
                GridView1.DataSource = dt
                GridView1.DataBind()

                If dt.Rows.Count > 0 Then
                    Dim i As Integer = 0

                    For Each row As GridViewRow In GridView1.Rows
                        Dim lblname As Label = TryCast(row.FindControl("lblcounty"), Label)
                        lblname.Text = dt.Rows(i)("Title").ToString()
                        i += 1
                    Next
                End If
            End Using
        End Using
    Else
        Me.BindGrid()
    End If
End Sub

Screenshot