--------------------------------------------------
// for ConnectionStrings
        StringBuilder sb1 = new StringBuilder();
        ConnectionStringSettingsCollection nv1 = WebConfigurationManager.ConnectionStrings as ConnectionStringSettingsCollection;
        IEnumerator oEnum = nv1.GetEnumerator();

        sb1.Append("<br><br>ConnectionStrings:<br>");
        int i = 0;
        while (oEnum.MoveNext())
        {
            string sKey = nv1[i].Name;
            sb1.Append(String.Format("{0}={1}.<br>", sKey, nv1[sKey]));
            i += 1;

        }

        ShowMsg(sb1.ToString());

--------------------------------------------------
// For AppSettings:

        StringBuilder sb1 = new StringBuilder();
        NameValueCollection nv1 = WebConfigurationManager.AppSettings as NameValueCollection;

        sb1.Append("<br><br>By foreach string: (Suggest)<br>");
        foreach (string sKey in nv1)
            sb1.Append(String.Format("{0}={1}.<br>", sKey, nv1[sKey]));

        sb1.Append("<br><br>By IEnumerator:<br>");
        IEnumerator oEnum = nv1.GetEnumerator();
        int i = 0;
        while (oEnum.MoveNext())
        {
            string sKey = nv1.AllKeys[i].ToString();
            sb1.Append(String.Format("{0}={1}.<br>",sKey, nv1[sKey]));
            i += 1;

        }


        ShowMsg(sb1.ToString());


--------------------------------------------------
// Show the use of AppSettings. 
// It gets the section from the configuration 
// file located at the application current level. 
static void GetAppSettings()
{

    // Get the appSettings key,value pairs collection.
    NameValueCollection appSettings =
        WebConfigurationManager.AppSettings
        as NameValueCollection;

    // Get the collection enumerator.
    IEnumerator appSettingsEnum =
        appSettings.GetEnumerator();

    // Loop through the collection and 
    // display the appSettings key, value pairs.
    int i = 0;
    Console.WriteLine("[Display appSettings]");
    while (appSettingsEnum.MoveNext())
    {
        string key = appSettings.AllKeys[i].ToString();
        Console.WriteLine("Key: {0} Value: {1}",
        key, appSettings[key]);
        i += 1;
    }

    Console.WriteLine();
}