Gridview的条件格式在行选择后不工作

我有一个gridview，根据单元格值有条件地格式化。当页面加载时，它工作得很好，但是当我选择一行时，它为所有行的第一个给定条件(黑色)格式化它。下面是条件格式的代码。

 //Conditionally formats the gridview to show banner colors
protected void EmployeeAchievementsGV_RowCreated(object sender, GridViewRowEventArgs e)
{
    //Black Banner
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int CellValue = Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "TotalAchievementsEarned"));
        if (CellValue >= 0 && CellValue < 12)
        {
            e.Row.BackColor = Color.Black;
            e.Row.Cells[0].ForeColor = Color.White;
            e.Row.Cells[1].ForeColor = Color.White;
            e.Row.Cells[2].ForeColor = Color.White;
        }
    }
    //Yellow Banner
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int CellValue = Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "TotalAchievementsEarned"));
        if (CellValue >= 12 && CellValue < 24)
        {
            e.Row.BackColor = Color.Yellow;
            e.Row.Cells[0].ForeColor = Color.Black;
            e.Row.Cells[1].ForeColor = Color.Black;
            e.Row.Cells[2].ForeColor = Color.Black;
        }
    }
    //Blue Banner
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int CellValue = Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "TotalAchievementsEarned"));
        if (CellValue >= 24 && CellValue < 36)
        {
            e.Row.BackColor = Color.DodgerBlue;
            e.Row.Cells[0].ForeColor = Color.White;
            e.Row.Cells[1].ForeColor = Color.White;
            e.Row.Cells[2].ForeColor = Color.White;
        }
    }
    //Orange Banner
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int CellValue = Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "TotalAchievementsEarned"));
        if (CellValue >= 36 && CellValue < 48)
        {
            e.Row.BackColor = Color.Orange;
            e.Row.Cells[0].ForeColor = Color.Black;
            e.Row.Cells[1].ForeColor = Color.Black;
            e.Row.Cells[2].ForeColor = Color.Black;
        }
    }
    //Pink Banner
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int CellValue = Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "TotalAchievementsEarned"));
        if (CellValue >= 48)
        {
            e.Row.BackColor = Color.HotPink;
            e.Row.Cells[0].ForeColor = Color.Black;
            e.Row.Cells[1].ForeColor = Color.Black;
            e.Row.Cells[2].ForeColor = Color.Black;
        }
    }
}

任何可能导致问题或如何解决问题的帮助将是伟大的。