专家坐堂-如何该表二维码的颜色，需要根据不同的业务形成不同颜色的二维码Foxtable(狐表) - 新一代数据库软件，完美融合Access、Foxpro、Excel、vb.net之优势，人人都能掌握的快速软件开发工具!

Public Function ChangeColour(ByVal img As Bitmap, ByVal inColourR As Byte, ByVal inColourG As Byte, ByVal inColourB As Byte, ByVal outColourR As Byte, ByVal outColourG As Byte, ByVal outColourB As Byte) As Bitmap

Dim bmp As new Bitmap(img.Width, img.Height, System.Drawing.Imaging.PixelFormat.Format32bppRgb)

using gr = Graphics.FromImage(bmp)

gr.DrawImage(img, new Rectangle(0, 0, img.Width, img.Height))

End using

Dim pxf As PixelFormat = PixelFormat.Format24bppRgb

Dim rect As Rectangle = New Rectangle(0, 0, bmp.Width, bmp.Height)

Dim bmpData As BitmapData = bmp.LockBits(rect, ImageLockMode.ReadWrite, pxf)

Dim ptr As IntPtr = bmpData.Scan0

Dim numBytes As Integer = Math.Abs(bmpdata.Stride) * bmp.Height

Dim rgbValues As Byte() = New Byte(numBytes - 1) {}

Marshal.Copy(ptr, rgbValues, 0, numBytes)

Dim a As Byte = 40

For counter As Integer = 0 To rgbValues.Length - 1 Step 3

If Math.Abs(rgbValues(counter) - inColourB) < a AndAlso Math.Abs(rgbValues(counter + 1) - inColourG) < a AndAlso Math.Abs(rgbValues(counter + 2) - inColourR) < a Then

rgbValues(counter) = outColourB

rgbValues(counter + 1) = outColourG

rgbValues(counter + 2) = outColourR

End If

Marshal.Copy(rgbValues, 0, ptr, numBytes)

bmp.UnlockBits(bmpData)

Return bmp

End Function

调用方法

Dim img As image = getImage("D:\\问题\\2.png") \'原图

Dim bmp As bitmap = ChangeColour(img ,0,0,0,65,105,255) \'第一个参数为传入的图片,第2~5个参数为原图颜色rgb值，默认为黑色。最后3个参数为需要替换的颜色rgb值，这里是r=65,g=105,b=255

bmp.save("D:\\问题\\3.png",img.RawFormat)

bmp.Dispose

bmp = ChangeColour(img ,0,0,0,255,0,0) \'这里替换为红色，也就是r=255,g=0,b=0

bmp.save("D:\\问题\\4.png",img.RawFormat)

bmp.Dispose