protected void Button1_Click(object sender, EventArgs e) { if (TextBox1.Text.Length == 0) { Label1.Visible = true; Label2.Visible = false; } else if (TextBox2.Text.Length == 0) { Label1.Visible = false; Label2.Visible = true; } else { Label1.Visible = Label2.Visible = false; if (s.Login(TextBox1.Text, TextBox2.Text)) { Session["username"] = TextBox1.Text; Session["dmlxpd"] = "gm"; Response.Redirect("Main.aspx"); } else { Response.Write("<script>alert('用户名或密码错误!')</script>"); } } }