使用DataSource绑定一维数组时，DataTextField只需绑定空字符串

方法定义：

 public static void InitDropDownList(DropDownList ddl, bool isAddTopItem, DropDownList ddlSub, object ddlDataSource, string ddlTextField, string ddlValueField)
 {
     ddl.DataSource = ddlDataSource;
     ddl.DataTextField = ddlTextField;
     ddl.DataValueField = ddlValueField;
     ddl.DataBind();
     if (isAddTopItem)
         ddl.Items.Insert(, new ListItem("--All--", ""));
     if (ddlSub != null)
         ddlSub.Items.Insert(, new ListItem("--All--", ""));
 }

使用方式：

 XXClass.InitDropDownList(ddlAvailableFieldEnter, false, null, new string[]{"field1","field2","field3"}, "", "");