VB.net 锁屏幕

文件: Wintalk.vb ' ' 摘要: 演示如何使用.NET Framework library创建聊天程序. ' '===================================================================== Option Explicit On Option Strict On Imports System Imports System.IO Imports System.Text Imports System.Threading Imports System.Net Imports System.Net.Sockets Imports System.Drawing Imports System.Windows.Forms Imports Microsoft.VisualBasic Class App 'Entry point which delegates to C-style main Private Function Public Overloads Shared Sub Main() Main(System.Environment.GetCommandLineArgs()) End Sub ' Entry point Overloads Public Shared Sub Main(args() As String) ' If the args parse in known way then run the app If ParseArgs(args) Then ' Create a custom Talker object Dim talkerObj As New Talker(endPoint, client) ' Pass the object reference to a new form object Dim form As New TalkForm(talkerObj) ' Start the talker "talking" talkerObj.Start() ' Run the applications message pump Application.Run(form) End If End Sub 'Main ' Parsed Argument Storage Private Shared endPoint As IPEndPoint Private Shared client As Boolean ' Parse command line arguments Private Shared Function ParseArgs(args() As String) As Boolean Try If args.Length = 1 Then client = False endPoint = New IPEndPoint(IPAddress.Any, 5150) Return True End If Dim port As Integer Select Case Char.ToUpper(args(1).ToCharArray()(1)) Case "L"c port = 5150 If args.Length > 2 Then port = Convert.ToInt32(args(2)) End If endPoint = New IPEndPoint(IPAddress.Any, port) client = False Case "C"c port = 5150 Dim address As String = "127.0.0.1" client = True If args.Length > 2 Then address = args(2) port = Convert.ToInt32(args(3)) End If endPoint = New IPEndPoint(Dns.Resolve(address).AddressList(0), port) Case Else ShowUsage() Return False End Select Catch End Try Return True End Function 'ParseArgs ' Show sample usage Private Shared Sub ShowUsage() MessageBox.Show("WinTalk [switch] [parameters...]" & ControlChars.CrLf & ControlChars.CrLf & _ " /L [port]" & ControlChars.Tab & ControlChars.Tab & "-- Listens on a port. Default: 5150" & ControlChars.CrLf & _ " /C [address] [port]" & ControlChars.Tab & "-- Connects to an address and port." & ControlChars.CrLf & ControlChars.CrLf & _ "Example Server - " & ControlChars.CrLf & _ "Wintalk /L" & ControlChars.CrLf & ControlChars.CrLf & _ "Example Client - " & ControlChars.CrLf & _ "Wintalk /C ServerMachine 5150", "WinTalk Usage") End Sub 'ShowUsage End Class 'App ' UI class for the sample Class TalkForm Inherits Form Public Sub New(talkerObj As Talker) ' Associate for method with the talker object Me.talkerObj = talkerObj AddHandler talkerObj.Notifications, AddressOf HandleTalkerNotifications ' Create a UI elements Dim talkSplitter As New Splitter() Dim talkPanel As New Panel() receiveText = New TextBox() sendText = New TextBox() 'we'll support up to 64k data in our text box controls receiveText.MaxLength = 65536 sendText.MaxLength = 65536 statusText = New Label() ' Initialize UI elements receiveText.Dock = DockStyle.Top receiveText.Multiline = True receiveText.ScrollBars = ScrollBars.Both receiveText.Size = New Size(506, 192) receiveText.TabIndex = 1 receiveText.Text = "" receiveText.WordWrap = False receiveText.ReadOnly = True talkPanel.Anchor = AnchorStyles.Top Or AnchorStyles.Bottom Or AnchorStyles.Left Or AnchorStyles.Right talkPanel.Controls.AddRange(New Control() {sendText, talkSplitter, receiveText}) talkPanel.Size = New Size(506, 371) talkPanel.TabIndex = 0 talkSplitter.Dock = DockStyle.Top talkSplitter.Location = New Point(0, 192) talkSplitter.Size = New Size(506, 6) talkSplitter.TabIndex = 2 talkSplitter.TabStop = False statusText.Dock = DockStyle.Bottom statusText.Location = New Point(0, 377) statusText.Size = New Size(507, 15) statusText.TabIndex = 1 statusText.Text = "Status:" sendText.Dock = DockStyle.Fill sendText.Location = New Point(0, 198) sendText.Multiline = True sendText.ScrollBars = ScrollBars.Both sendText.Size = New Size(506, 173) sendText.TabIndex = 0 sendText.Text = "" sendText.WordWrap = False AddHandler sendText.TextChanged, AddressOf HandleTextChange sendText.Enabled = False AutoScaleBaseSize = New Size(5, 13) ClientSize = New Size(507, 392) Controls.AddRange(New Control() {statusText, talkPanel}) Me.Text = "WinTalk" Me.ActiveControl = sendText End Sub 'New ' When the app closes, dispose of the talker object Protected Overrides Sub OnClosed(e As EventArgs) If Not (talkerObj Is Nothing) Then RemoveHandler talkerObj.Notifications, AddressOf HandleTalkerNotifications talkerObj.Dispose() End If MyBase.OnClosed(e) End Sub 'OnClosed ' Handle notifications from the talker object Private Sub HandleTalkerNotifications(notify As Talker.Notification, data As Object) Select Case notify Case Talker.Notification.Initialized ' Respond to status changes Case Talker.Notification.StatusChange Dim statusObj As Talker.Status = CType(data, Talker.Status) statusText.Text = String.Format("Status: {0}", statusObj) If statusObj = Talker.Status.Connected Then sendText.Enabled = True End If ' Respond to received text Case Talker.Notification.Received receiveText.Text = data.ToString() receiveText.SelectionStart = Int32.MaxValue receiveText.ScrollToCaret() ' Respond to error notifications Case Talker.Notification.ErrorNotify Close(data.ToString()) ' Respond to end Case Talker.Notification.EndNotify MessageBox.Show(data.ToString(), "Closing WinTalk") Close() Case Else Close() End Select End Sub 'HandleTalkerNotifications ' Handle text change notifications and send talk Private Sub HandleTextChange(sender As Object, e As EventArgs) If Not (talkerObj Is Nothing) Then talkerObj.SendTalk(CType(sender, TextBox).Text) End If End Sub 'HandleTextChange ' Close with an explanation Private OverLoads Sub Close(message As String) MessageBox.Show(message, "Error!") Close() End Sub 'Close ' Private UI elements Private receiveText As Te