显示排序信息.txt

来自「C# 是创新性的新式编程语言」· 文本 代码 · 共 39 行

//重新排序
		private void UpdateDataView()
		{
			DataSet ds=(DataSet)Session["MyDataSet"];
			DataView dv=ds.Tables["MyList"].DefaultView;
			dv.Sort=(string)ViewState["SortExpression"];
			if(ViewState["SortAscending"].ToString()=="no")
				dv.Sort+=" DESC";
			ViewState["ColSort"]=dv.Sort;//记录排序表达式
			DataGrid1.DataSource=dv;
			DataGrid1.DataBind();
		}

		private void DataGrid1_ItemCreated(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
		{
			ListItemType elemType=e.Item.ItemType;//获得被创建项的类型
			if(elemType==ListItemType.Header)
			{
				string strSortBy=(string)ViewState["SortExpression"];
				string strSortAscending=(string)ViewState["SortAscending"];
				string strOrder=(strSortAscending=="yes"?"5":"6");//对于webdings字体,5为向上箭头,6为向下箭头
				for(int i=0;i<DataGrid1.Columns.Count;i++)
				{
					TableCell cell=e.Item.Cells[i];
					//添加排充表达式提示
					if(DataGrid1.Columns[i].SortExpression!="")
						cell.ToolTip="Sort by:"+(ViewState["ColSort"]==null?(DataGrid1.Columns[i].SortExpression):ViewState["ColSort"].ToString());					
					if(strSortBy==DataGrid1.Columns[i].SortExpression)
					{
						//增加一个(升序或降序的)符号
						Label lblSorted=new Label();
						lblSorted.Font.Name="webdings";
						lblSorted.Font.Size=FontUnit.XSmall;
						lblSorted.Text=strOrder;
						cell.Controls.Add(lblSorted);
					}
				} 
			}
		}