Imports System.Drawing.Imaging
Imports System.Drawing
Imports System.Runtime.InteropServices
Public Class Form1

Dim ScreenWidth As Integer = Screen.PrimaryScreen.Bounds.Width  '获取屏幕宽度  
Dim ScreenHeight As Integer = Screen.PrimaryScreen.Bounds.Height '获取屏幕高度  

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    Dim bmp As Bitmap = New Bitmap(ScreenWidth, ScreenHeight)  '创建一个和屏幕大小相同的Bitmap图片对象  

    Dim g As Graphics = Graphics.FromImage(bmp)  '从该位图创建Graphics对象  

    g .CopyFromScreen(0, 0, 0, 0, bmp .Size)  '将整个桌面的内容绘制到我们新建的位图上（也就是截图）  

    bmp .Save("D:\test\screencapture" & Now() & ".jpg", ImageFormat .Jpeg )  '保存我们新绘制的位图（也就是截图）  

    g .Dispose()  '释放Graphics对象  

End Sub

End Class