//================再把来ＸＭＬ文档，以ＸＭＬ形式显示在ListBox里面

 双击"ＸＭＬ文档" 写进下面这些代码:

  ListBox1.Items.Clear()

'''' 清空listBox
        Dim xtr As XmlTextReader = New XmlTextReader("myxml.xml")

''''创建成一个XmlTextReader读取"myxml.xml"文档
        While xtr.Read
            Select Case (xtr.NodeType)

       '''' 咱们用select case 形式来选择xml节点类型
                Case XmlNodeType.XmlDeclaration

      ''''先从ListBox里写进xml声明=====xmldeclaration
                    ListBox1.Items.Add("<?xml version=''''1.0'''' encoding=''''gb2312''''?>")

   ''''再依次显示节点的名称，值

   ''''包括根节点
                Case XmlNodeType.Element
                    ListBox1.Items.Add("<" & xtr.Name & ">")
                Case XmlNodeType.Text
                    ListBox1.Items.Add(xtr.Value)
                Case XmlNodeType.EndElement
                    ListBox1.Items.Add("</" & xtr.Name & ">")

            End Select
        End While
        xtr.Close()

 ''''关闭xmlTextReader

  //========再把数据库中所有数据显示在ListBox中========

  ''''双击"查看全部"按钮

 ''''写入下面的一些代码:

 ListBox1.Items.Clear()

 ''''这些代码大家应该可以看得懂了
        OleDbConnection1.Open()
        Dim selall As String
        selall = "select * from users"
        OleDbCommand1 = New OleDbCommand
        Me.OleDbCommand1.CommandText = selall
        Me.OleDbCommand1.Connection = OleDbConnection1
        Try
            Dim creader As OleDbDataReader = OleDbCommand1.ExecuteReader()
            While creader.Read
                ListBox1.Items.Add("name: " & creader("nameid").ToString() & "; age :" & creader("age").ToString() & "; faverity :" & creader("faverity").ToString())
            End While
            creader.Close()
        Catch ex As Exception
            ListBox1.Items.Add("Errors")
        End Try
        OleDbConnection1.Close()

  //==========================再来进完成删除按钮=================

  ''''双击"删除"按钮

  ''''写入以下的代码

  If TextBox4.Text <> "" Then

''''如果不为空，进行以下操作
            ListBox1.Items.Clear()

   ''''先清空ListBox
            OleDbConnection1.Open()

  '''' 建立连接
            Dim delstring As String
            delstring = TextBox4.Text
            Dim delsel As String
            delsel = "select * from users where nameid=''''" & delstring & "''''"

  ''''创建查询字符串
            OleDbCommand1 = New OleDbCommand
            Me.OleDbCommand1.CommandText = delsel
            Me.OleDbCommand1.Connection = OleDbConnection1
            Try
                Dim selreader As OleDbDataReader = OleDbCommand1.ExecuteReader()
                If Not selreader.Read Then

  ''''假如读不到，就表明数据库无此数据，无法进行删除操作
                    MessageBox.Show("数据库中无该记录!")
                Else
                    selreader.Close()

   ''''要对数据进行操作，必须首把DataReader关掉
                    Dim delrecord As String
                    delrecord = "delete * from users where nameid=''''" & delstring & "''''"

   ''''建立删除字符串sql语句，以上都是
                    OleDbCommand1 = New OleDbCommand
                    Me.OleDbCommand1.CommandText = delrecord
                    Me.OleDbCommand1.Connection = OleDbConnection1
                    Me.OleDbCommand1.ExecuteNonQuery()
                    MessageBox.Show("删除成功!!")

  ''''再把进行删除操作的数据库，再次把数据库中数据保存成ＸＭＬ文档
                    DataSet1 = New DataSet
                    OleDbDataAdapter1 = New OleDbDataAdapter("select * from users", OleDbConnection1)
                    OleDbDataAdapter1.Fill(DataSet1, "users")
                    DataSet1.WriteXml("myxml.xml")
                End If
            Catch ex As Exception
                MessageBox.Show(ex.Message)
            Finally
                OleDbConnection1.Close()
            End Try
        Else
            MessageBox.Show("请输入你想删除的记录!")
        End If

 //======================= 重设按钮=====

  TextBox1.Text = ""
        TextBox2.Text = ""
        TextBox3.Text = ""
        ListBox1.Items.Clear()

 //============================关闭===============

            me.Close()

''''好了这个小软件完成了，有问题的话留言

''''本程序在.net framework 2003创建

''''已经进行过测试，完全可以运行

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