admin_book_list.aspx.vb

《ASP.NET C#程序设计案例教程》

Imports Microsoft.VisualBasic

Public Class admin_book_list
    Inherits System.Web.UI.Page

#Region " Web 窗体设计器生成的代码 "

    '该调用是 Web 窗体设计器所必需的。
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

    End Sub
    Protected WithEvents myDataGrid As System.Web.UI.WebControls.DataGrid
    Protected WithEvents Form1 As System.Web.UI.HtmlControls.HtmlForm

    '注意: 以下占位符声明是 Web 窗体设计器所必需的。
    '不要删除或移动它。
    Private designerPlaceholderDeclaration As System.Object

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: 此方法调用是 Web 窗体设计器所必需的
        '不要使用代码编辑器修改它。
        InitializeComponent()
    End Sub

#End Region

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        '在此处放置初始化页的用户代码
        '判断一下，如果不是管理员，就返回到首页
        If DataUserLog.IsAdmin() = False Then
            Response.Write("<script language='javascript'>top.document.location='../index.aspx';</script>")
        End If

        If Not Page.IsPostBack Then
            Call myDataBind()          '绑定数据
        End If
    End Sub
    '该过程用于绑定数据
    Sub myDataBind()
        '下面建立DataBusiness对象，返回所有文章
        Dim dbs As New DataBusiness
        Dim dv As DataView = dbs.GetBook()
        '下面绑定数据
        myDataGrid.DataSource = dv
        myDataGrid.DataBind()
    End Sub

    '该过程用于删除行，不过要注意其中会判断是最后一页，且只有一行的情况
    Private Sub myDataGrid_DeleteCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles myDataGrid.DeleteCommand
        Dim dbs As New DataBusiness
        dbs.DeleteBook(myDataGrid.DataKeys(e.Item.ItemIndex))

        '下面先判断是否是最后一页，且只有一行的情况
        If myDataGrid.PageCount > 1 And myDataGrid.CurrentPageIndex = (myDataGrid.PageCount - 1) And myDataGrid.Items.Count = 1 Then
            myDataGrid.CurrentPageIndex = myDataGrid.CurrentPageIndex - 1
        End If

        '重新绑定数据
        Call myDataBind()
    End Sub
    '该过程用于添加删除确认框
    Private Sub myDataGrid_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles myDataGrid.ItemDataBound
        '这个判断语句表示，只有对于数据行才执行，对于标题栏和脚注栏则不执行
        If e.Item.ItemType <> ListItemType.Header And e.Item.ItemType <> ListItemType.Footer Then
            '下面找到删除按钮控件，它其实是一个LinkButton控件
            Dim lbtnDel As LinkButton     '定义一个LinkButton控件
            lbtnDel = e.Item.Cells(7).Controls(0) '它位于第7列第0个控件
            '下面添加JavaScript事件
            lbtnDel.Attributes.Add("onclick", "javascript:return confirm('您真的要删除 " & e.Item.DataItem("BookName") & " 吗？');")
        End If
    End Sub
    '该过程用于分页
    Private Sub myDataGrid_PageIndexChanged(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridPageChangedEventArgs) Handles myDataGrid.PageIndexChanged
        myDataGrid.CurrentPageIndex = e.NewPageIndex
        Call myDataBind()
    End Sub
End Class