我的系統之前就有這麼個問題，當兩個圖片重疊的時候，上面的圖片總是將下面的圖片覆蓋，之前因為忙一直沒有騰出時間處理一下

今天實在看不下去了，然後本來想自己重新寫一個，但是問了技術群的大佬，給重寫了一個PictureBoxDE 類，效果如下

 完美的解決了圖片的透明，下面我將把這個重寫的類發出來，供大家使用參考，也順便做一下記錄

 1 public class ReiongCtr : PictureBox
 2     {
 3         protected override void OnSizeChanged(EventArgs e)
 4         {
 5
 
             base.OnSizeChanged(e);
 6             if (BackgroundImage != null)
 7             {
 8                 Bitmap bit = (Bitmap)BackgroundImage.GetThumbnailImage(Width, Height, null, IntPtr.Zero);
 9                 Region = ImageToRegion(bit, Color.FromArgb(0, 0, 0, 0));
10             }
11         }
 
12         protected override void OnBackgroundImageChanged(EventArgs e)
13         {
14             base.OnBackgroundImageChanged(e);
15             if (BackgroundImage != null)
16             {
17                 Bitmap bit = (Bitmap)BackgroundImage.GetThumbnailImage(Width, Height, null, IntPtr.Zero);
 
18                 Region = ImageToRegion(bit, Color.FromArgb(0, 0, 0, 0));
19             }
20         }
21          
22         /// <summary>
23         /// 根據圖片計算Region路徑(低效率)
24         /// </summary>
25         /// <param name="img">影象資源</param>
26         /// <param name="TranColor">欲透明掉的顏色</param>
27         /// <returns>一個離散的路徑資訊</returns>
28         public static Region ImageToRegion(Image imgx, Color TranColor)
29         {
30             if (imgx == null) return null;
31             Region rRegion = new Region();
32             rRegion.MakeEmpty();
33 
34 
35             int ImWidth = imgx.Width;
36             int ImHeight = imgx.Height;
37             Color curColor;
38             Rectangle curRect = new Rectangle();
39             curRect.Height = 1;
40             bool isTransRgn;
41 
42             for (int y = 0; y < ImHeight; y++)
43             {
44                 isTransRgn = true;
45                 for (int x = 0; x < ImWidth; x++)
46                 {
47                     curColor = ((Bitmap)imgx).GetPixel(x, y);
48                     if (curColor == TranColor || x == ImWidth - 1)//如果遇到透明色或行尾
49                     {
50                         if (isTransRgn == false)//退出有效區
51                         {
52                             curRect.Width = x - curRect.X;
53                             rRegion.Union(curRect);
54                         }
55                     }
56                     else//非透明色
57                     {
58                         if (isTransRgn == true)//進入有效區
59                         {
60                             curRect.X = x;
61                             curRect.Y = y;
62                         }
63                     }//if curColor
64                     isTransRgn = curColor == TranColor;
65                 }
66             }
67             return rRegion;
68         }
69     }