asp.net|标准

在asp.net 2.0下，gridview是十分方便的了，加一个DATASOURCE系列的控件的话，就可以马上和gridview绑定，十分方便。但其实也可以
使用datatable或者dataview的，这个时候就不是用datasource系列控件了。下面讲下如何在asp.net 2.0下，实现gridview控件的翻页，各列排序，
编辑的功能。
    首先，我们读取的是northwind数据库中的employee表。放置一个gridview后，添加几个绑定的列，代码如下
 <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，我们要实现分页，把AllowPaging设置为true,并设置每页的分页条数，最后在codebehind中写入
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        GridView1.PageIndex = e.NewPageIndex;
        BindGrid();
    }
  为了实现每列都可以自动点击排序，可以设置allowsorting=true,然后设置OnSorting="GridView1_Sorting"，其中gridview_sorting
代码为
  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();
    }
很明显，设置viewsate来保存每次排序时的顺序，上面的相信很容易理解。
     最后，实现编辑功能，因为在aspx页面中已经设置了OnRowEditing="GridView1_RowEditing"，其中GridView1_RowEditing的代码为
 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 where ", 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，上面的代码和asp.net 1.1版本的其实原理是差不多的。最后，bindgrid()的过程很简单，为绑定咯
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();

这里gridview绑定的是dataview,并且用dv.sort设定了每次排序的顺序，也就是说，每次排序后其顺序都是保持不变的。
当然最后是page_load事件咯
   protected void Page_Load(object sender, EventArgs e)
    {
        if(!IsPostBack)
        {
            BindGrid();
        }
    }