Select RadioButtonList Item by matching TextBox value in ASP.Net

Hi vyas,

Please take reference the below code and change your code.

Database

I have made use of the table Customers. You can download the database table SQL by clicking the download link below.

Download SQL file

HTML

Customer:<asp:DropDownList ID="ddlCustomers" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlCustomers_SelectedIndexChanged">
</asp:DropDownList>
<br />
Name:
<asp:TextBox ID="txtName" runat="server"></asp:TextBox>
<br />
Country:
<asp:RadioButtonList ID="rblCountries" runat="server">
</asp:RadioButtonList>

Namespaces

C#

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

VB.Net

Imports System.Data.SqlClient

Code

C#

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

protected void ddlCustomers_SelectedIndexChanged(object sender, EventArgs e)
{
    string customerID = ddlCustomers.SelectedItem.Value;
    this.PopulateCountriesRadioButtonList();
    string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT Name,Country FROM Customers WHERE CustomerId = @CustomerId", con))
        {
            con.Open();
            cmd.Parameters.AddWithValue("@CustomerId", customerID);
            SqlDataReader dr = cmd.ExecuteReader();
            if (dr.Read())
            {
                txtName.Text = dr["Name"].ToString();
            }
            if (rblCountries.Items.FindByText(dr["Country"].ToString()) != null)
            {
                rblCountries.Items.FindByText(dr["Country"].ToString()).Selected = true;
            }
            con.Close();
        }
    }
}

private void PopulateCustomersDropDownList()
{
    string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("select CustomerID, Name from Customers", con))
        {
            con.Open();
            ddlCustomers.DataSource = cmd.ExecuteReader();
            ddlCustomers.DataTextField = "Name";
            ddlCustomers.DataValueField = "CustomerID";
            ddlCustomers.DataBind();
            con.Close();
        }
    }
}
private void PopulateCountriesRadioButtonList()
{
    string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    SqlConnection con = new SqlConnection(constr);
    SqlCommand cmd = new SqlCommand("SELECT DISTINCT Country FROM Customers", con);
    con.Open();
    rblCountries.DataSource = cmd.ExecuteReader();
    rblCountries.DataTextField = "Country";
    rblCountries.DataValueField = "Country";
    rblCountries.DataBind();
    con.Close();
}

VB.Net

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

Protected Sub ddlCustomers_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
    Dim customerID As String = ddlCustomers.SelectedItem.Value
    Me.PopulateCountriesRadioButtonList()
    Dim constr As String = ConfigurationManager.ConnectionStrings("conString").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT Name,Country FROM Customers WHERE CustomerId = @CustomerId", con)
            con.Open()
            cmd.Parameters.AddWithValue("@CustomerId", customerID)
            Dim dr As SqlDataReader = cmd.ExecuteReader()
            If dr.Read() Then
                txtName.Text = dr("Name").ToString()
            End If
            If rblCountries.Items.FindByText(dr("Country").ToString()) IsNot Nothing Then
                rblCountries.Items.FindByText(dr("Country").ToString()).Selected = True
            End If
            con.Close()
        End Using
    End Using
End Sub

Private Sub PopulateCustomersDropDownList()
    Dim constr As String = ConfigurationManager.ConnectionStrings("conString").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("select CustomerID, Name from Customers", con)
            con.Open()
            ddlCustomers.DataSource = cmd.ExecuteReader()
            ddlCustomers.DataTextField = "Name"
            ddlCustomers.DataValueField = "CustomerID"
            ddlCustomers.DataBind()
            con.Close()
        End Using
    End Using
End Sub

Private Sub PopulateCountriesRadioButtonList()
    Dim constr As String = ConfigurationManager.ConnectionStrings("conString").ConnectionString
    Dim con As SqlConnection = New SqlConnection(constr)
    Dim cmd As SqlCommand = New SqlCommand("SELECT DISTINCT Country FROM Customers", con)
    con.Open()
    rblCountries.DataSource = cmd.ExecuteReader()
    rblCountries.DataTextField = "Country"
    rblCountries.DataValueField = "Country"
    rblCountries.DataBind()
    con.Close()
End Sub

Screenshot