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Public Class Form1
Inherits System.Windows.Forms.Form
Dim bmp As New Bitmap(800, 600)
#Region " Windows 窗体设计器生成的代码 "

Public Sub New()
MyBase.New()

'该调用是 Windows 窗体设计器所必需的。
InitializeComponent()

'在 InitializeComponent() 调用之后添加任何初始化

End Sub

'窗体重写 dispose 以清理组件列表。
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub

'Windows 窗体设计器所必需的
Private components As System.ComponentModel.IContainer

'注意: 以下过程是 Windows 窗体设计器所必需的
'可以使用 Windows 窗体设计器修改此过程。
'不要使用代码编辑器修改它。
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents PictureBox1 As System.Windows.Forms.PictureBox
Friend WithEvents Button2 As System.Windows.Forms.Button
Friend WithEvents Button3 As System.Windows.Forms.Button
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents Timer1 As System.Windows.Forms.Timer
Friend WithEvents Timer2 As System.Windows.Forms.Timer
Friend WithEvents saved As System.Windows.Forms.SaveFileDialog
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.components = New System.ComponentModel.Container
Me.Button1 = New System.Windows.Forms.Button
Me.PictureBox1 = New System.Windows.Forms.PictureBox
Me.Button2 = New System.Windows.Forms.Button
Me.Button3 = New System.Windows.Forms.Button
Me.Label1 = New System.Windows.Forms.Label
Me.Timer1 = New System.Windows.Forms.Timer(Me.components)
Me.Timer2 = New System.Windows.Forms.Timer(Me.components)
Me.saved = New System.Windows.Forms.SaveFileDialog
Me.SuspendLayout()
'
'Button1
'
Me.Button1.BackColor = System.Drawing.Color.Purple
Me.Button1.Font = New System.Drawing.Font("华文新魏", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
Me.Button1.ForeColor = System.Drawing.Color.FromArgb(CType(0, Byte), CType(192, Byte), CType(0, Byte))
Me.Button1.Location = New System.Drawing.Point(16, 216)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(72, 24)
Me.Button1.TabIndex = 0
Me.Button1.Text = "抓屏"
'
'PictureBox1
'
Me.PictureBox1.BackColor = System.Drawing.Color.Red
Me.PictureBox1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
Me.PictureBox1.Location = New System.Drawing.Point(24, 16)
Me.PictureBox1.Name = "PictureBox1"
Me.PictureBox1.Size = New System.Drawing.Size(248, 176)
Me.PictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.StretchImage
Me.PictureBox1.TabIndex = 1
Me.PictureBox1.TabStop = False
'
'Button2
'
Me.Button2.BackColor = System.Drawing.Color.Purple
Me.Button2.Font = New System.Drawing.Font("华文新魏", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
Me.Button2.ForeColor = System.Drawing.Color.FromArgb(CType(0, Byte), CType(192, Byte), CType(0, Byte))
Me.Button2.Location = New System.Drawing.Point(208, 216)
Me.Button2.Name = "Button2"
Me.Button2.Size = New System.Drawing.Size(72, 24)
Me.Button2.TabIndex = 2
Me.Button2.Text = "退出"
'
'Button3
'
Me.Button3.BackColor = System.Drawing.Color.Purple
Me.Button3.Font = New System.Drawing.Font("华文新魏", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
Me.Button3.ForeColor = System.Drawing.Color.FromArgb(CType(0, Byte), CType(192, Byte), CType(0, Byte))
Me.Button3.Location = New System.Drawing.Point(112, 216)
Me.Button3.Name = "Button3"
Me.Button3.Size = New System.Drawing.Size(72, 24)
Me.Button3.TabIndex = 3
Me.Button3.Text = "保存"
'
'Label1
'
Me.Label1.AutoSize = True
Me.Label1.Font = New System.Drawing.Font("宋体", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
Me.Label1.ForeColor = System.Drawing.Color.Maroon
Me.Label1.Location = New System.Drawing.Point(208, 248)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(0, 22)
Me.Label1.TabIndex = 4
'
'Timer1
'
Me.Timer1.Interval = 1000
'
'Timer2
'
Me.Timer2.Interval = 50
'
'saved
'
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
Me.BackColor = System.Drawing.Color.FromArgb(CType(255, Byte), CType(255, Byte), CType(128, Byte))
Me.ClientSize = New System.Drawing.Size(296, 270)
Me.Controls.Add(Me.Label1)
Me.Controls.Add(Me.Button3)
Me.Controls.Add(Me.Button2)
Me.Controls.Add(Me.PictureBox1)
Me.Controls.Add(Me.Button1)
Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
Me.MaximizeBox = False
Me.MinimumSize = New System.Drawing.Size(302, 302)
Me.Name = "Form1"
Me.Opacity = 0
Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
Me.Text = "捕捉电脑屏幕"
Me.ResumeLayout(False)

End Sub

#End Region
Private Declare Function CreateCompatibleDC Lib "GDI32" (ByVal hDC As Integer) As Integer
Private Declare Function CreateCompatibleBitmap Lib "GDI32" (ByVal hDC As Integer, ByVal nWidth As Integer, ByVal nHeight As Integer) As Integer
Private Declare Function SelectObject Lib "GDI32" (ByVal hDC As Integer, ByVal hObject As Integer) As Integer
Private Declare Function BitBlt Lib "GDI32" (ByVal srchDC As Integer, ByVal srcX As Integer, ByVal srcY As Integer, ByVal srcW As Integer, ByVal srcH As Integer, ByVal desthDC As Integer, ByVal destX As Integer, ByVal destY As Integer, ByVal op As Integer) As Integer
Private Declare Function DeleteDC Lib "GDI32" (ByVal hDC As Integer) As Integer
Private Declare Function DeleteObject Lib "GDI32" (ByVal hObj As Integer) As Integer
Private Declare Function GetDC Lib "user32" Alias "GetDC" (ByVal hwnd As Integer) As Integer
Const SRCCOPY As Integer = &HCC0020
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Form1.ActiveForm.Opacity = 0
Dim hDC, hMDC As Integer
Dim hBMP, hBMPOld As Integer
Dim sw, sh As Integer
hDC = GetDC(0)
hMDC = CreateCompatibleDC(hDC)
sw = Screen.PrimaryScreen.Bounds.Width
sh = Screen.PrimaryScreen.Bounds.Height
hBMP = CreateCompatibleBitmap(hDC, sw, sh)
hBMPOld = SelectObject(hMDC, hBMP)
BitBlt(hMDC, 0, 0, sw, sh, hDC, 0, 0, SRCCOPY)
hBMP = SelectObject(hMDC, hBMPOld)
PictureBox1.Image = Image.FromHbitmap(New IntPtr(hBMP))
DeleteDC(hDC)
DeleteDC(hMDC)
DeleteObject(hBMP)
Form1.ActiveForm.Opacity = 1
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Timer2.Enabled = True
End
End Sub

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Label1.Text = TimeOfDay
End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Timer2.Enabled = True
End Sub

Private Sub Timer2_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer2.Tick
If Form1.ActiveForm.Opacity < 1 Then
Form1.ActiveForm.Opacity = Form1.ActiveForm.Opacity + 0.02
ElseIf Form1.ActiveForm.Opacity = 1 Then
Timer2.Enabled = False
End If
End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
bmp = New Bitmap(PictureBox1.Image)
saved.Filter = "*.bmp|*.bmp"
saved.FileName = "图片名"
saved.ShowDialog()
If saved.FileName <> "" Then
bmp.Save(saved.FileName)
Me.Text = saved.FileName
End If
End Sub

End Class