GridView 排序

这两天搞gridview 排序，发现gridview只有指定DataSourceid的时候才支持。因为datatable不主持排序，如果数据源是datatable的话需要自己定义。网上很多，方法到也很简单，记录做个备忘

 <asp:GridView ID="GView" runat="server" AutoGenerateColumns="false" AllowPaging="true" 
      OnPageIndexChanging="GView_PageIndexChanging"  AllowSorting="true" 
           onsorting="GView_Sorting">
            <Columns>
                <asp:BoundField HeaderText="指标名称" DataField="showname" />
                <asp:BoundField HeaderText="计量单位" DataField="itemunit" ItemStyle-HorizontalAlign="Center" />
                <asp:BoundField HeaderText="偏差" DataField="chrData" ItemStyle-HorizontalAlign="Right" DataFormatString="{0:#0.0%}"  SortExpression="chrData" />   //设置需要排序的列
            </Columns>
        </asp:GridView>
//指定Gridview运行排序，

 后台CS代码

//主要代码
    protected void GView_Sorting(object sender, GridViewSortEventArgs e)
    {
        GridViewSortExpression = e.SortExpression;

        GView.DataSource = SortDataTable((DataTable)GView.DataSource, false);
        GView.DataBind();

    }
//可以针对分页和不分页分别设置
 protected void GView_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        GView.PageIndex = e.NewPageIndex;       
        GView.DataSource = SortDataTable((DataTable)GView.DataSource, true);
        GView.DataBind();
    }
    private string GridViewSortDirection //设置属性，默认ASC
    {
        get { return ViewState["SortDirection"] == null ? "ASC" : ViewState["SortDirection"].ToString(); }
        set { ViewState["SortDirection"] = value; }
    }
    private string GridViewSortExpression
    {
        get { return ViewState["SortExpression"] == null ? "" : ViewState["SortExpression"].ToString(); }
        set { ViewState["SortExpression"] = value; }
    }
    private string GetSortDirection() //设置排序
    {
        switch (GridViewSortDirection)
        {
            case "ASC":

                GridViewSortDirection = "DESC";
                break;
            case "DESC":
                GridViewSortDirection = "ASC";
                break;
        }
        return GridViewSortDirection;
    }
 //根据DataView 排序
    protected DataView SortDataTable(DataTable dataTable, bool isPageIndexChanging)
    {
        if (dataTable != null)
        {
            DataView dataView = new DataView(dataTable);
            if (GridViewSortExpression != string.Empty)
            {
                if (isPageIndexChanging)
                {
                    dataView.Sort = string.Format("{0} {1}", GridViewSortExpression, GridViewSortDirection);
                }
                else
                {
                    dataView.Sort = string.Format("{0} {1}", GridViewSortExpression, GetSortDirection());
                }
            }
            return dataView;
        }

        else
        {
            return new DataView();
        }

    }