NET属性没有得到正确设置

嗨，我有一个类，下面给出。{BR​​}

public partial class myClass : System.Web.UI.Page

{

    // FC is freight center

    private string selectedState; 

    private string selectedCity; 

    private string stateLatitude;

    private string stateLongitude; 

...

 

   below given properties go here..

}

protected void ShowMap(object sender, EventArgs e)

{

     use public properties here.. but the values of properties StateLatitude and StateLongitude are getting set to empty or "" when the button on aspx page is clicked and it enters this function.

}