C byte*到vb.net bitmapdata scanline

元帅是这里唯一的路。我以前做过很多成功的事,但这是在涂油。

http://msdn.microsoft.com/en-us/library/system.drawing.imaging.bitmapdata.scan0.aspx

' Get the address of the first line.
Dim ptr As IntPtr = bmpData.Scan0

' Declare an array to hold the bytes of the bitmap.
' This code is specific to a bitmap with 24 bits per pixels.
Dim bytes As Integer = Math.Abs(bmpData.Stride) * bmp.Height
Dim rgbValues(bytes - 1) As Byte

' Copy the RGB values into the array.
System.Runtime.InteropServices.Marshal.Copy(ptr, rgbValues, 0, bytes)

VB.NET中不支持指针。只要vb.net是您的需求,marshal类就是您所能得到的,那么其他的选择就非常缓慢。不必如此,在您的解决方案中添加一个C类库,并在您的vb.net代码中使用它的类在Visual Studio中得到了很好的支持。

这是我的确切信息,但一次通过就失败了。关于数组越界的一些信息,可能是y*bmd.stride的一些信息(但我不明白为什么会出现越界错误,因为它应该只复制原始内存字节,不使用数组!)

  Public Function findImages(ByVal bmd As BitmapData) As List(Of Point)
    Dim results As New List(Of Point)()
    foundRects = New List(Of Rectangle)()

    For y As Integer = 0 To bmd.Height - 1
        'oringinal code
        'Dim scanline As Pointer(Of Byte) = CType(bmd.Scan0, Pointer(Of Byte)) + (y * bmd.Stride)

        'mess is here
        ' gets address of the first line
        'Dim ptr As IntPtr = bmd.Scan0
        'Dim bytes As Integer = (y * bmd.Stride)
        'If bytes = 0 Then bytes = bmd.Stride
        Dim scanline(bmd.Width * PIXLESIZE) As Byte

        'Copy the RGB values into the array.
        Runtime.InteropServices.Marshal.Copy(bmd.Scan0, scanline, (y * bmd.Stride), bmd.Width * PIXLESIZE)
        ' --------------------------------

        For x As Integer = 0 To bmd.Width - 1
            Dim xo As Integer = x * PIXLESIZE
            Dim buff As Byte() = {scanline(xo), scanline(xo + 1), scanline(xo + 2), &HFF}
            Dim val As Integer = BitConverter.ToInt32(buff, 0)

            ' Pixle value from subimage in desktop image
            If pixels.ContainsKey(val) AndAlso notFound(x, y) Then
                Dim loc As Point = DirectCast(pixels(val), Point)

                Dim sx As Integer = x - loc.X
                Dim sy As Integer = y - loc.Y
                ' Subimage occurs in desktop image 
                If imageThere(bmd, sx, sy) Then
                    Dim p As New Point(x - loc.X, y - loc.Y)
                    results.Add(p)
                    foundRects.Add(New Rectangle(x, y, bmImage.Width, bmImage.Height))
                End If
            End If
        Next
    Next

    Return results
End Function