验证GridView控件在编辑状态下输入的数据是否合法（不合法，不允许更新，同时弹出提示框）

ReadOnly="true"，表示该列不能被编辑

页面设计：

<table style="border:solid 1px green;40%">
            <tr>
                <td style="background-color:Green"><strong><span style="font-size: 14pt; color: #ffffff">验证GridView控件中编辑列的值</span></strong>
                </td>
            </tr>
            <tr>
                <td>
                    <asp:GridView Width="100%" ID="GridView1" runat="server" AutoGenerateColumns="False" CellPadding="4" ForeColor="#333333" GridLines="None" OnRowCancelingEdit="GridView1_RowCancelingEdit" OnRowDataBound="GridView1_RowDataBound" OnRowEditing="GridView1_RowEditing" OnRowUpdating="GridView1_RowUpdating" DataKeyNames="ProductID">
                        <Columns>
                           <asp:BoundField DataField="ProductName" ReadOnly="True" HeaderText="商品名称"/>
                            <asp:TemplateField>
                                <HeaderTemplate>
                                    <table width="100%">
                                        <tr>
                                            <td align="left" width="60%" >数量</td>
                                        </tr>
                                    </table>
                                </HeaderTemplate>
                                <ItemTemplate>
                                    <table width="100%">
                                        <tr>
                                            <td width="20%"><%# Eval("UnitsInStock")%></td>
                                        </tr>
                                    </table>
                                </ItemTemplate>
                                <EditItemTemplate>
                                    <table>
                                        <tr>
                                            <td width="20%"><asp:TextBox runat="Server" ID="t1" Text='<%# Eval("UnitsInStock")%>' Width="90%"></asp:TextBox></td>
                                        </tr>
                                    </table>
                                </EditItemTemplate>
                            </asp:TemplateField>
                            <asp:CommandField ShowEditButton="True" HeaderText="操作" />
                        </Columns>
                        <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
                        <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
                        <EditRowStyle BackColor="#999999" />
                        <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
                        <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
                        <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
                    </asp:GridView>
                </td>
            </tr>
        </table>　

后台代码：

“编辑”事件处理代码：

protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
    {
        this.GridView1.EditIndex = -1;           //        获取编辑行的索引值
        band();        // 会绑数据
    }

当用户进入编辑状态，在文本框中输入内容后，“更新”，会触发 RowDataBound事件进行校验用户输入的数据，代码如下：

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if ((e.Row.RowState & DataControlRowState.Edit)==DataControlRowState.Edit)
        {
            RequiredFieldValidator re = new RequiredFieldValidator();   // 创建一个非空验证控件
            re.ControlToValidate = "t1";
            re.ErrorMessage = "销售量不能为空";
            re.Display = ValidatorDisplay.Dynamic;
            re.Text = "*";
            e.Row.Cells[1].Controls.Add(re);              //           将该空间添加到GridView控件中
            RangeValidator ra = new RangeValidator();
            ra.ControlToValidate = "t1";
            ra.Type = ValidationDataType.Integer;
            ra.Display = ValidatorDisplay.Dynamic;
            ra.MaximumValue = "200";
            ra.MinimumValue = "10";
            ra.Text = "*";
            ra.ErrorMessage = "销售量的范围为10-200";
            e.Row.Cells[1].Controls.Add(ra);
            ValidationSummary va = new ValidationSummary();        //    创建一个范围验证控件
            va.ShowSummary = false;
            va.ShowMessageBox = true;
            e.Row.Cells[1].Controls.Add(va);               //    添加到GridView中
        }
    }

验证无误后，触发 RowUpdating 事件，代码如下：

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["val"].ConnectionString);
        con.Open();
        string aa = this.GridView1.DataKeys[e.RowIndex].Value.ToString();
        string bb = ((TextBox)this.GridView1.Rows[e.RowIndex].Cells[0].FindControl("t1")).Text.ToString();
        string cc = "update products set UnitsInStock='" + bb + "' where ProductID='" + aa +"'";
        SqlCommand cmd = new SqlCommand(cc, con);
        cmd.ExecuteNonQuery();
        con.Close();
        this.GridView1.EditIndex = -1;
        band();
        Response.Write("<script>alert('更新成功！')</script>");
    }