asp.net 2.0下一個標準GRIDVIEW功能的實現（不用datasource控制項）

在asp.net 2.0下，gridview是十分方便的了，加一個DATASOURCE系列的控制項的話，就可以馬上和gridview綁定，十分方便。但其實也可以
使用datatable或者dataview的，這個時候就不是用datasource系列控制項了。下面講下如何在asp.net 2.0下，實現gridview控制項的翻頁，各列排序，
編輯的功能。
    首先，我們讀取的是northwind資料庫中的employee表。放置一個gridview後，添加幾個綁定的列，代碼如下
 <asp:GridView ID="GridView1" runat="server" AllowPaging="True" AllowSorting="True"
            AutoGenerateColumns="False" CellPadding="4" ForeColor="#333333" GridLines="None"
            Width="100%" DataKeyNames="EmployeeID" OnPageIndexChanging="GridView1_PageIndexChanging" OnRowEditing="GridView1_RowEditing" OnRowUpdating="GridView1_RowUpdating" OnSorting="GridView1_Sorting" PageSize="3" OnRowCancelingEdit="GridView1_RowCancelingEdit" OnRowCommand="GridView1_RowCommand">
            <FooterStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />
            <Columns>
                <asp:BoundField DataField="employeeid" HeaderText="Employee ID" ReadOnly="True" />
                <asp:BoundField DataField="firstname" HeaderText="First Name" SortExpression="firstname" />
                <asp:BoundField DataField="lastname" HeaderText="Last Name" SortExpression="lastname" />
                <asp:CommandField ShowEditButton="True" />
            </Columns>
            <RowStyle BackColor="#FFFBD6" ForeColor="#333333" />
            <SelectedRowStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="Navy" />
            <PagerStyle BackColor="#FFCC66" ForeColor="#333333" HorizontalAlign="Center" />
            <HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />
            <AlternatingRowStyle BackColor="White" />
        </asp:GridView>

首先，我們要實現分頁，把AllowPaging設定為true,並設定每頁的分頁條數，最後在codebehind中寫入
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        GridView1.PageIndex = e.NewPageIndex;
        BindGrid();
    }
  為了實現每列都可以自動點擊排序，可以設定allowsorting=true,然後設定OnSorting="GridView1_Sorting"，其中gridview_sorting
代碼為
  protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
    {
        ViewState["sortexpression"] = e.SortExpression;

        if (ViewState["sortdirection"] == null)
        {
            ViewState["sortdirection"] = "asc";
        }
        else
        {
            if (ViewState["sortdirection"].ToString() == "asc")
            {
                ViewState["sortdirection"] = "desc";
            }
            else
            {
                ViewState["sortdirection"] = "asc";
            }
        }
        BindGrid();
    }
很明顯，設定viewsate來儲存每次排序時的順序，上面的相信很容易理解。
     最後，實現編輯功能，因為在aspx頁面中已經設定了OnRowEditing="GridView1_RowEditing"，其中GridView1_RowEditing的代碼為
 protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        int empid;
        string fname, lname;
        empid = int.Parse(GridView1.Rows[e.RowIndex].Cells[0].Text);
        fname = ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text;
        lname = ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text;

        SqlConnection cnn = new SqlConnection(@"data source=localhost;initial catalog=northwind;user id=sa;password=123456");
        cnn.Open();
        SqlCommand cmd = new SqlCommand("update employees set firstname=@fname,lastname=@lname where employeeid=@empid", cnn);
        cmd.Parameters.Add(new SqlParameter("@fname",fname));
        cmd.Parameters.Add(new SqlParameter("@lname", lname));
        cmd.Parameters.Add(new SqlParameter("@empid", empid));
        cmd.ExecuteNonQuery();
        cnn.Close();

        GridView1.EditIndex = -1;
        BindGrid();
    }
    protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
    {
        GridView1.EditIndex = e.NewEditIndex;
        BindGrid();
    }
    protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        GridView1.EditIndex = -1;
        BindGrid();
    }

  可以看到，上面的代碼和asp.net 1.1版本的其實原理是差不多的。最後，bindgrid()的過程很簡單，為綁定咯
DataSet ds = new DataSet();
        SqlDataAdapter da = new SqlDataAdapter("select * from employees", @"data source=localhost;initial catalog=northwind;user id=sa;password=123456");
        da.Fill(ds,"employees");
        DataView dv = ds.Tables[0].DefaultView;

        if (ViewState["sortexpression"] != null)
        {
            dv.Sort = ViewState["sortexpression"].ToString() + " " + ViewState["sortdirection"].ToString();
        }

        GridView1.DataSource=dv;
        GridView1.DataBind();

這裡gridview綁定的是dataview,並且用dv.sort設定了每次排序的順序，也就是說，每次排序後其順序都是保持不變的。
當然最後是page_load事件咯
   protected void Page_Load(object sender, EventArgs e)
    {
        if(!IsPostBack)
        {
            BindGrid();
        }
    }