Gridview进入编辑状态，新手来看。

可能是学习能力有限吧，我从昨晚到今天，累积起来起码五六个小时，才终于弄懂了这个Gridview的编辑。毕竟找来的代码都是没有注释和说明的。

我想记录下来，也希望后来的新丁能少走弯路。

 <form id="form1" runat="server">
    <div class="div1">
        <asp:GridView ID="GridView1" Width="100%" AutoGenerateColumns="False" runat="server" DataKeyNames="Sid"
            OnRowEditing="GridView1_RowEditing" OnRowUpdating="GridView1_RowUpdating"  OnRowCancelingEdit="GridView1_RowCancelingEdit" BackColor="White" BorderColor="#DEDFDE" BorderStyle="None" BorderWidth="1px" CellPadding="4" ForeColor="Black" GridLines="Vertical">
            <AlternatingRowStyle BackColor="White" />
          <Columns>
              <asp:BoundField DataField="Sid" HeaderText="学号"/>
              <asp:BoundField DataField="Sname" HeaderText="姓名" />
              <asp:BoundField DataField="Sage" HeaderText="年龄" />
              <asp:BoundField DataField="Sphone" HeaderText="电话" />
              <asp:BoundField DataField="Spwd" HeaderText="密码" />
              <asp:CommandField ShowDeleteButton="true" HeaderText="操作" />
              <asp:CommandField ShowEditButton="true" HeaderText="操作" />
          </Columns>
            <FooterStyle BackColor="#CCCC99" />
            <HeaderStyle BackColor="#6B696B" Font-Bold="True" ForeColor="White" />
            <PagerStyle BackColor="#F7F7DE" ForeColor="Black" HorizontalAlign="Right" />
            <RowStyle BackColor="#F7F7DE" />
            <SelectedRowStyle BackColor="#CE5D5A" Font-Bold="True" ForeColor="White" />
            <SortedAscendingCellStyle BackColor="#FBFBF2" />
            <SortedAscendingHeaderStyle BackColor="#848384" />
            <SortedDescendingCellStyle BackColor="#EAEAD3" />
            <SortedDescendingHeaderStyle BackColor="#575357" />
        </asp:GridView>
    </div>
    </form>

protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                BindData();
            }
        }
        private void BindData()
        {
            string sql = string.Format("select * from Student");
            DataTable dt = SqlHelper.ExctuteDataTable(sql);
            GridView1.DataSource = dt;
            GridView1.GridLines = GridLines.Both;
            GridView1.RowStyle.HorizontalAlign = HorizontalAlign.Center;//单元格文字居中
            GridView1.DataBind();

            GridView1.EditRowStyle.ForeColor = Color.Red;
        }
        protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
        {
            GridView1.EditIndex = e.NewEditIndex;
            BindData();
        }

        protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            /*先获得所要编辑的行的第0号单元格里的第一个子控件，转成TextBox类型然后取值*/
            int Sid = int.Parse(((TextBox)GridView1.Rows[e.RowIndex].Cells[0].Controls[0]).Text.ToString().Trim());

            /*FindControl里的参数填控件的id，但我们需要先获取这个id，所以不推荐这种用法。*/
            //string Sname = (GridView1.Rows[e.RowIndex].Cells[0].FindControl("Sname") as TextBox).Text;
            string Sname = ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text.ToString().Trim();
            string Sage = ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text.ToString().Trim();
            string Sphone = ((TextBox)GridView1.Rows[e.RowIndex].Cells[3].Controls[0]).Text.ToString().Trim();
            string Spwd = ((TextBox)GridView1.Rows[e.RowIndex].Cells[4].Controls[0]).Text.ToString().Trim();
            string sql = string.Format("update Student set Sid={0},Sname=‘{1}‘,Sage=‘{2}‘,Sphone=‘{3}‘,Spwd=‘{4}‘where Sid={5}",
                Sid, Sname, Sage, Sphone, Spwd, int.Parse(GridView1.DataKeys[e.RowIndex].Value.ToString()));
            SqlHelper.ExecuteNonQuery(sql);
        }

        protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
        {
            GridView1.EditIndex = -1;
            BindData();
        }