Topic: Setting image to clipboard problem.

[BillZndl]

AutoCAD 2012, VS2010 Express, NET 3.5

Anyone have an idea of why after using the clipboard in the program,
autocad locks up as soon as I try to open a different drawing and displays the message:
"Unhandled Exception: System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt”
The program works fine, multiple times, copying & pasting (using cntrl + V), until I try to open another drawing in SDI=1.

As soon as I rem out the clipboard line, all is well.
Do I need to dispose of something or clear the clipboard?

Code - C#: [Select]

1.  private void button2_Click(object sender, EventArgs e)
2.         {
3.             try
4.             {
5.                 pictureBox1.Image = null;
6.                 pictureBox1.Image = DrawPartInPicBox.PartImage(pictureBox1.Width, pictureBox1.Height); //creates bitmap image
7.                 pictureBox1.Update();
8.                 //Clipboard.SetImage(pictureBox1.Image); <------ this line is the culprit.
9.             }
10.             catch (Exception exc)
11.             {
12.                 MessageBox.Show("Error : " + exc.InnerException);
13.             }
14.            
15.         }

TIA!

Bill

[Andrey Bushman]

Can you publish the code sources of the simple"HelloWorld" project which exactly demonstrates your problem?

[BillZndl]

Can you publish the code sources of the simple"HelloWorld" project which exactly demonstrates your problem?

Not easily.
But while looking things over, I discovered that I had created a definition of an ImageList, in the form code.

private ImageList ImgLst = new ImageList(); (no other reference to this in the code).

It never seemed to cause a problem until I added the line for the clipboard.setImage.
Now that I removed the imagelist reference, I can no longer duplicate the error. 


I'll attach the netloadable .dll.
Command name : "ShowPic"

Simple form show with select entities button.
Displays selection in picturebox.Image.

[mohnston]

Is it possible that you have a reference to the image instead of a new image? Maybe try clone?
pictureBox1.Image = DrawPartInPicBox.PartImage(pictureBox1.Width, pictureBox1.Height).Clone();

[BillZndl]

Is it possible that you have a reference to the image instead of a new image? Maybe try clone?
pictureBox1.Image = DrawPartInPicBox.PartImage(pictureBox1.Width, pictureBox1.Height).Clone();

I don't think so.
The method "PartImage" returns a new bitmap image.

Code - C#: [Select]

1. public static Bitmap PartImage(int width, int height)
2.         {
3.             ArrayList EntPnts = new ArrayList();
4.             List<string> LaLst = new List<string> { };
5.            
6.             GetPointsFromEntityIDs(ref LaLst, ref EntPnts, width, height);   //points from AutoCAD entities.
7.  
8.             Bitmap image = new Bitmap(width, height);
9.  
10.             Graphics graphics = Graphics.FromImage(image);
11.             graphics.Clear(Color.Black);
12.  
13.             if (EntPnts.Count == 0)  //empty list.
14.             {
15.                 graphics.DrawString("Nothing Selected: ", new System.Drawing.Font("Romans", 28f), Brushes.DarkCyan, (PointF)new Point(8, height / 2));
16.             }
17.  
18.             if (EntPnts.Count > 0)  //converted pointF[]'s to draw.
19.             {
20.                 int num = 0;
21.  
22.                 foreach (PointF[] PntFarray in EntPnts)         //draw each entity from point set.
23.                 {
24.                     string Layer = LaLst[num];                  //color of layer entity is on.
25.                     num++;                    
26.  
27.                     switch (Layer)
28.                     {
29.                         case "0":
30.                         case "BEND":
31.                             graphics.DrawLines(new Pen(Brushes.White), PntFarray);
32.                             break;
33.  
34.                         case "LDRILL":
35.                             graphics.DrawLines(new Pen(Brushes.Cyan), PntFarray);
36.                             break;
37.  
38.                         case "NAIL":
39.                             graphics.DrawLines(new Pen(Brushes.Yellow), PntFarray);
40.                             break;
41.  
42.                         case "OUTSIDE":
43.                             graphics.DrawLines(new Pen(Brushes.Red), PntFarray);
44.                             break;
45.  
46.                         case "PH":
47.                             graphics.DrawLines(new Pen(Brushes.OrangeRed), PntFarray);
48.                             break;
49.  
50.                         case "CLEAR":
51.                             graphics.DrawLines(new Pen(Brushes.Lime), PntFarray);
52.                             break;
53.  
54.                         case "HID":
55.                             graphics.DrawLines(new Pen(Brushes.Magenta), PntFarray);
56.                             break;
57.  
58.                         default:
59.                             graphics.DrawLines(new Pen(Brushes.White), PntFarray);
60.                             break;
61.                     }
62.  
63.                 }
64.  
65.                 graphics.Dispose();
66.             }
67.  
68.             return image;
69.         }