C#ASP.NET继承

我如何继承这个类，当我试图继承它时，它给了我一个错误

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class expresion2 : System.Web.UI.Page
{
    public String nombre, email, telefono, contra, usuario;

    protected void Page_Load(object sender, EventArgs e)
    {
        nombre = txtNombre.Text;
        email = txtEmail.Text;
        telefono = txtTel.Text;
        contra = txtContra.Text;
        usuario = txtUser.Text;


    }
}

当我尝试继承“expresion2”时，它在VS studio 2016上给了我一个编译错误

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class mostrar2 : expresion2
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
}

---

您的mostrar2和expression2类未在命名空间中定义

正确的定义如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace myNamespace
{
    public partial class expresion2 : System.Web.UI.Page
    {
        public String nombre, email, telefono, contra, usuario;

        protected void Page_Load(object sender, EventArgs e)
        {
            nombre = txtNombre.Text;
            email = txtEmail.Text;
            telefono = txtTel.Text;
            contra = txtContra.Text;
            usuario = txtUser.Text;


        }
    }
}

及

---

您的mostrar2和expression2类未在命名空间中定义

正确的定义如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace myNamespace
{
    public partial class expresion2 : System.Web.UI.Page
    {
        public String nombre, email, telefono, contra, usuario;

        protected void Page_Load(object sender, EventArgs e)
        {
            nombre = txtNombre.Text;
            email = txtEmail.Text;
            telefono = txtTel.Text;
            contra = txtContra.Text;
            usuario = txtUser.Text;


        }
    }
}

及

---

它不起作用！仍然给出相同的错误，有没有其他方法可以将变量从expresion2继承到mostra2？它不起作用！仍然给出相同的错误，是否有其他方法将变量从expresion2继承到mostra2？