dropdownlist绑定数据函数 dropdownlist控件绑定数据

从数据库中读出一组数据，要求把数据绑定在dropdownlist上：

/// <summary>
/// DropDownList
/// </summary>
public class DropDownlist
{
    /// <summary>
    /// DropDownList绑定数据
    /// <para>--------------说明------------------</para>
    /// <para>DataTable dt = GetAllDatas("select id,uid from tests");</para>
    /// <para>select语句中应该有两列，第一列为text,第二列为value</para>
    /// <para>.BindData(dt, DropDownList1,"请选择","-1");</para>
    /// <para>------------------------------------</para>
    /// </summary>
    /// <param name="dtdata">数据源datatable 第一列为文本，第二列是值</param>
    /// <param name="s">DropDownList的ID</param>
    public string BindData(DataTable dtdata, DropDownList s)
    {
        return BindData(dtdata, s, "", "");
    }

    /// <summary>
    /// DropDownList绑定数据
    /// <para>--------------说明------------------</para>
    /// <para>DataTable dt = GetAllDatas("select id,uid from tests");</para>
    /// <para>select语句中应该有两列，第一列为text,第二列为value</para>
    /// <para>.BindData(dt, DropDownList1,"请选择","-1");</para>
    /// <para>------------------------------------</para>
    /// </summary>
    /// <param name="dtdata">数据源datatable 第一列为文本，第二列是值</param>
    /// <param name="s">DropDownList的ID</param>
    /// <param name="FirstLineText">在最上面加一个固定标题项，如“请选择”</param>
    public string BindData(DataTable dtdata, DropDownList s, string FirstLineText)
    {
        return BindData(dtdata, s, FirstLineText, "-1");
    }

    /// <summary>
    /// DropDownList绑定数据
    /// <para>--------------说明------------------</para>
    /// <para>DataTable dt = GetAllDatas("select id,uid from tests");</para>
    /// <para>select语句中应该有两列，第一列为text,第二列为value</para>
    /// <para>.BindData(dt, DropDownList1,"请选择","-1");</para>
    /// <para>------------------------------------</para>
    /// </summary>
    /// <param name="dtdata">数据源datatable 第一列为文本，第二列是值</param>
    /// <param name="s">DropDownList的ID</param>
    /// <param name="FirstLineText">在最上面加一个固定标题项，如“请选择”</param>
    /// <param name="FirstLineValue">加行的值，默认-1</param>
    public string BindData(DataTable dtdata, DropDownList s, string FirstLineText, string FirstLineValue)
    {
        try
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("text");
            dt.Columns.Add("value");

            if (FirstLineText.Length != 0)
            {
                DataRow dr1 = dt.NewRow();
                dr1["text"] = FirstLineText;
                dr1["value"] = FirstLineValue;
                dt.Rows.Add(dr1);
            }

            for (int i = 0; i < dtdata.Rows.Count; i++)
            {
                string text = dtdata.Rows[i][0].ToString().Trim();
                string value = dtdata.Rows[i][1].ToString().Trim();

                DataRow dr = dt.NewRow();
                dr["text"] = text;
                dr["value"] = value;
                dt.Rows.Add(dr);
            }

            s.DataTextField = "text";
            s.DataValueField = "value";
            s.DataSource = dt;
            s.DataBind();

            return "OK";
        }
        catch (Exception ErrMsg)
        {
            Error((int)FunctionNames.Control__XLLB__Dropdownlist, ErrMsg.ToString());
            return ErrMsg.ToString();
        }
    }
}