自定義的排序方法了,今天學習到了如何用dataset搭配gridview的話,進行標題排序,現將其方法摘錄如下:
首先,用一個方法將數據取出來,放到DATASET裏去,如下代碼
private DataSet GetData()
{
SqlConnection myConnection = new SqlConnection(ConnectionString);
SqlDataAdapter ad = new SqlDataAdapter("SELECT * FROM Categories", myConnection);
DataSet ds = new DataSet();
ad.Fill(ds);
return ds;
}
然後,對gridview進行如下設置
<asp:GridView ID="GridView1" runat="server" AllowSorting="True" OnSorting="GridView1_Sorting">
</asp:GridView>
然後,其gridview_sorting的自定義過程如下,首先添加一個屬性
public SortDirection GridViewSortDirection
{
get
{
if (ViewState["sortDirection"] == null)
ViewState["sortDirection"] = SortDirection.Ascending;
return (SortDirection) ViewState["sortDirection"];
}
set { ViewState["sortDirection"] = value; }
}
GridViewSortDirection 是一個簡單的屬性,用viewstate保存每次排序的方向
而GridView1_Sorting的代碼如下:
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
string sortExpression = e.SortExpression;
if (GridViewSortDirection == SortDirection.Ascending)
{
GridViewSortDirection = SortDirection.Descending;
SortGridView(sortExpression, DESCENDING);
}
else
{
GridViewSortDirection = SortDirection.Ascending;
SortGridView(sortExpression, ASCENDING);
}
}
在這裏,首先得到用戶點擊要排序列的標題,然後判斷當前gridviewsortdirection的屬性值來判斷,如果已經是升序的話,則設置GridViewSortDirection爲降序,並調用一個sortgridview過程;否則默認是調用升序來排序;
而sortgridview方法如下:
private void SortGridView(string sortExpression,string direction)
{
DataTable dt = GetData().Tables[0];
DataView dv = new DataView(dt);
dv.Sort = sortExpression + direction;
GridView1.DataSource = dv;
GridView1.DataBind();
}
在這裏,接收兩個參數,分別是sortExpression和direction,然後構成dataview進行排序,十分好理解