验证用户名是否已经回答并显示数据库ASPC＃

Question

我将此表格用于回答的用户名：

<table>
    <tr><td><b>User:</b></td><td><asp:Label ID="useren" runat="server"></asp:Label></td></tr> 
    <tr><td><b>Business:</b></td><td><asp:TextBox ID="business" runat="server" MaxLength="13"></asp:TextBox> (Example: +351234925xxx)</td></tr>
    <tr><td><b>Business 2:</b></td><td><asp:TextBox ID="business2" runat="server" MaxLength="4"></asp:TextBox> (Example: xxxx)</td></tr>
    <tr><td><b>Mobile:</b></td><td><asp:TextBox ID="mobile" runat="server" MaxLength="13"></asp:TextBox> (Example: +3519xxxxxxxx)</td></tr>
    <tr><td colspan="2"><asp:Label ID="Label1" runat="server" Font-Bold="True"></asp:Label></td></tr>
    <tr><td><asp:Button ID="Button1" runat="server" Text="Save" onclick="cmdSave_Click2" /></td><td></td></tr>
</table>

要从windows login-user获取用户名，我在后面的代码中有这个：

protected void Page_Load(object sender, EventArgs e)
{
    useren.Text = "[" + HttpContext.Current.User.Identity.Name + "]";
}

并将所有text.box从表保存到ACCESS DataBase我有：

protected void cmdSave_Click2(object sender, EventArgs e)
    {
        string sFilePath = Server.MapPath("Database3.accdb");
        OleDbConnection Conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + sFilePath + ";Persist Security Info=False;");
        string insertCmd = "INSERT INTO colaborador(Empresa,Empresa2,Telemovel,username) VALUES (@Empresa,@Empresa2,@Telemovel,@useren)";
        using (Conn)
        {
            Conn.Open();
            OleDbCommand myCommand = new OleDbCommand(insertCmd, Conn);
            myCommand.Parameters.AddWithValue("@Empresa", business.Text);
            myCommand.Parameters.AddWithValue("@Empresa2", business2.Text);
            myCommand.Parameters.AddWithValue("@Telemovel", mobile.Text);
            myCommand.Parameters.AddWithValue("@useren", HttpContext.Current.User.Identity.Name); 
            myCommand.ExecuteNonQuery(); 
            Label1.Text = "Saved Successfull!";
            Label1.ForeColor = System.Drawing.Color.Green;
        }
    }

但是如何检测如果用户已经已经回答，并说出“用户已经回答”或者例如。显示该用户的数据库存储数据， Else 显示创建的表格以显示text.box。