1. Customer Registration (CustomerRegistration.aspx.vb)

Partial Class CustomerRegistration
    Inherits System.Web.UI.Page

    Protected Sub btnRegister_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnRegister.Click
        Dim con As New SqlConnection("connection_string")
        Dim cmd As New SqlCommand("INSERT INTO Customer (Name, HouseNo, Street, PostalCode, Phone) VALUES (@n, @h, @s, @p, @ph)", con)

        cmd.Parameters.AddWithValue("@n", txtName.Text)
        cmd.Parameters.AddWithValue("@h", txtHouseNo.Text)
        cmd.Parameters.AddWithValue("@s", txtStreet.Text)
        cmd.Parameters.AddWithValue("@p", txtPostalCode.Text)
        cmd.Parameters.AddWithValue("@ph", txtPhone.Text)

        con.Open()
        cmd.ExecuteNonQuery()
        con.Close()
    End Sub
End Class

2. Customer Search (CustomerSearch.aspx.vb)

Partial Class CustomerSearch
    Inherits System.Web.UI.Page

    Protected Sub btnSearch_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnSearch.Click
        Dim con As New SqlConnection("connection_string")
        Dim cmd As New SqlCommand("SELECT * FROM Customer WHERE Name LIKE @name", con)
        cmd.Parameters.AddWithValue("@name", "%" & txtSearch.Text & "%")

        con.Open()
        Dim reader As SqlDataReader = cmd.ExecuteReader()
        GridView1.DataSource = reader
        GridView1.DataBind()
        con.Close()
    End Sub
End Class