webform1.aspx.vb

Visual Basic.NET应用编程150例

Public Class WebForm1
    Inherits System.Web.UI.Page
    Protected WithEvents OleDbConnection1 As System.Data.OleDb.OleDbConnection
    Protected WithEvents cmdIDAll As System.Data.OleDb.OleDbCommand
    Protected WithEvents cmdNameById As System.Data.OleDb.OleDbCommand
    Protected WithEvents cmdUpdate As System.Data.OleDb.OleDbCommand
    Protected WithEvents txtmemberName As System.Web.UI.WebControls.TextBox
    Protected WithEvents txtDescription As System.Web.UI.WebControls.TextBox
    Protected WithEvents memberIDList As System.Web.UI.WebControls.DropDownList
    Protected WithEvents btnSave As System.Web.UI.WebControls.Button

#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()
        Me.OleDbConnection1 = New System.Data.OleDb.OleDbConnection()
        Me.cmdIDAll = New System.Data.OleDb.OleDbCommand()
        Me.cmdNameById = New System.Data.OleDb.OleDbCommand()
        Me.cmdUpdate = New System.Data.OleDb.OleDbCommand()
        '
        'OleDbConnection1
        '
        Me.OleDbConnection1.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Password="""";User ID=Admin;Data Source=C:\Documen" & _
        "ts and Settings\Administrator\My Documents\Visual Studio Projects\ADDRBOOK.MDB;M" & _
        "ode=Share Deny None;Extended Properties="""";Jet OLEDB:System database="""";Jet OLED" & _
        "B:Registry Path="""";Jet OLEDB:Database Password="""";Jet OLEDB:Engine Type=5;Jet OL" & _
        "EDB:Database Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global" & _
        " Bulk Transactions=1;Jet OLEDB:New Database Password="""";Jet OLEDB:Create System " & _
        "Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDB:Don't Copy Locale on C" & _
        "ompact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False"
        '
        'cmdIDAll
        '
        Me.cmdIDAll.CommandText = "SELECT 成员编号, 名字, 业余爱好 FROM 家庭成员"
        Me.cmdIDAll.Connection = Me.OleDbConnection1
        '
        'cmdNameById
        '
        Me.cmdNameById.CommandText = "SELECT 成员编号, 名字, 业余爱好 FROM 家庭成员 WHERE (成员编号 = ?)"
        Me.cmdNameById.Connection = Me.OleDbConnection1
        Me.cmdNameById.Parameters.Add(New System.Data.OleDb.OleDbParameter("成员编号", System.Data.OleDb.OleDbType.Integer, 0, System.Data.ParameterDirection.Input, False, CType(10, Byte), CType(0, Byte), "成员编号", System.Data.DataRowVersion.Current, Nothing))
        '
        'cmdUpdate
        '
        Me.cmdUpdate.CommandText = "UPDATE 家庭成员 SET 名字 = ?, 业余爱好 = ? WHERE (成员编号 = ?)"
        Me.cmdUpdate.Connection = Me.OleDbConnection1
        Me.cmdUpdate.Parameters.Add(New System.Data.OleDb.OleDbParameter("名字", System.Data.OleDb.OleDbType.VarWChar, 50, "名字"))
        Me.cmdUpdate.Parameters.Add(New System.Data.OleDb.OleDbParameter("业余爱好", System.Data.OleDb.OleDbType.VarWChar, 255, "业余爱好"))
        Me.cmdUpdate.Parameters.Add(New System.Data.OleDb.OleDbParameter("Original_成员编号", System.Data.OleDb.OleDbType.Integer, 0, System.Data.ParameterDirection.Input, False, CType(10, Byte), CType(0, Byte), "成员编号", System.Data.DataRowVersion.Original, Nothing))

    End Sub

    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
        If Not IsPostBack Then
            Dim dreader As OleDb.OleDbDataReader
            OleDbConnection1.Open()
            dreader = cmdIDAll.ExecuteReader
            Dim firstrow As Boolean = True
            While dreader.Read()
                Me.memberIDList.Items.Add(New ListItem(dreader(0).ToString()))
                If firstrow Then
                    txtmemberName.Text = dreader(1).ToString
                    txtDescription.Text = dreader(2).ToString
                    firstrow = False
                End If
            End While
            dreader.Close()
            OleDbConnection1.Close()
        End If

    End Sub

    Private Sub memberID_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles memberIDList.SelectedIndexChanged
        cmdNameById.Parameters.Item(0).Value = CType(Me.memberIDList.SelectedItem.Text, Integer)
        OleDbConnection1.Open()
        Dim dreader As OleDb.OleDbDataReader
        dreader = cmdNameById.ExecuteReader(CommandBehavior.SingleRow)
        If dreader.Read() Then
            txtmemberName.Text = dreader(1)
            txtDescription.Text = dreader(2)
        End If
        dreader.Close()
        OleDbConnection1.Close()

    End Sub

    Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
        With cmdUpdate
            .Parameters(2).Value = CType(memberIDList.SelectedItem.Text, Integer)
            .Parameters(0).Value = txtmemberName.Text
            .Parameters(1).Value = txtDescription.Text
        End With
        OleDbConnection1.Open()
        cmdUpdate.ExecuteNonQuery()
        OleDbConnection1.Close()
    End Sub
End Class