vb.net 中，怎样获取内存中图片流的内存首地址及大小？

[良朋]

vb.net 中，怎样获取内存中图片流的内存首地址及大小？
Dim ms As System.IO.MemoryStream = New System.IO.MemoryStream(File.ReadAllBytes(mFileName))

我把一个图片文件以流的形式读入到内存中，怎样获取它的内存首地址及大小？

[红衣老大]

为啥要获取这个？ 要做操图片 没有也能做 另外 vb确实不擅长操作内存 如果一定的要作业的api了

[wxyong2sy]

fs = New FileStream(mFileName, FileMode.Open, IO.FileAccess.Read) Dim file(fs.Length-1) As Byte fs.Read(file, 0, fs.Length) fs.Close() 这是我读任意文件为二进制流的代码，对图片也一样。

[良朋]

这个可以，其实我是想把我用线扫相机扫到的buffer传递给visionPro的cogImage, 唉，一直找不到有关代码。

Private Sub LockUnlockBitsExample(ByVal e As PaintEventArgs)


        Dim bmp As New Bitmap("c:\fakePhoto.jpg")

        ' Lock the bitmap's bits.  
        Dim rect As New Rectangle(0, 0, bmp.Width, bmp.Height)
        Dim bmpData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rect, Drawing.Imaging.ImageLockMode.ReadWrite, bmp.PixelFormat)

        ' 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 = 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)

        ' Set every third value to 255. A 24bpp image will look red.
        For counter As Integer = 2 To rgbValues.Length - 1 Step 3
            rgbValues(counter) = 255
        Next

        ' Copy the RGB values back to the bitmap
        System.Runtime.InteropServices.Marshal.Copy(rgbValues, 0, ptr, bytes)

        ' Unlock the bits.
        bmp.UnlockBits(bmpData)

        ' Draw the modified image.
        e.Graphics.DrawImage(bmp, 0, 150)

    End Sub


    Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
        LockUnlockBitsExample(e)
    End Sub