总行数SqlDataSource GridView

所以我有一个GridView设置为SqlDataSource.分页已启用,我有一个下拉菜单,可以更改每页显示的行数.我能够在单个页面中显示总行数,但我还想显示总行数.(像这样:"显示315的1 - 25").

所以,我的问题是:

1)如何获取整个DataSource的总行数？(不只是GridView)我的代码OnSelectedData方法不起作用并返回零.

2)如何让每个页面的数字显示不同？例如,在第二页上,它需要说"显示26 - 50 of 315"

这是我的代码(C#):

public partial class UserControls_BloombergAllUsersControl : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{       
}
int gridViewTotalRowCount;
protected void onSelectedData(object sender, SqlDataSourceStatusEventArgs e)
{
    gridViewTotalRowCount = e.AffectedRows;
}
protected void GridView1_DataBound(object sender, EventArgs e)
{
    int pageRowsCount = GridView1.Rows.Count;

    Total1.Text = "Showing 1 - " + pageRowsCount.ToString() + " of " + gridViewTotalRowCount.ToString();
}
private void BindGridView1()
{
    try
    {
        this.GridView1.DataBind();

        if (Convert.ToInt32(DropDownList1.SelectedValue) != null)
            GridView1.PageSize = Convert.ToInt32(DropDownList1.SelectedValue);
    }
    catch (Exception ex)
    { throw ex; }
}
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
    GridView1.PageIndex = e.NewPageIndex;
    BindGridView1();
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
    BindGridView1();
}

}

如果有人能提供帮助,那就太好了.谢谢!