protected void Page_Load(object sender, EventArgs e)
    {
 
 
        Response.Write("sql is connected");
        SqlDataAdapter da = new SqlDataAdapter("select countryid,countryname from countryname", cn);
        DataSet ds = new DataSet();
        da.Fill(ds,"countryname");
        ddlcountryname.DataSource = ds.Tables["countryname"];
        ddlcountryname.DataTextField = "countryname";
        ddlcountryname.DataValueField = "countryid";
        ddlcountryname.DataBind();
 
 
    }
    protected void ddlcountryname_SelectedIndexChanged(object sender, EventArgs e)
    {
        string country_id;
        country_id = ddlcountryname.SelectedValue.ToString();
        SqlDataAdapter da1=new SqlDataAdapter("select stateid,statename from statename where countryid=' country_id'",cn);
        DataSet ds1 = new DataSet();
        da1.Fill(ds1, "statename");
        ddlstatename.DataSource = ds1.Tables["statename"];
        ddlstatename.DataTextField = "statename";
        ddlstatename.DataValueField = "stateid";
        ddlstatename.DataBind();
    }