. Net image Verification Code (C)

1. Create a chkcode. aspx and chkcode. aspx. CS Code as follows:

1. Using system;
2. Using system. drawing;
3. Using system. Drawing. imaging;
4. Using system. IO;
6. Public partial class chkcode: system. Web. UI. Page
7. {
8. Protected void page_load (Object sender, eventargs E)
9. {
10. Showimg ();
11. }
13. Private void showimg ()
14. {
15. Random ran = new random ();
16. Int intrandom = ran. Next (1001,999 9 );
17. // Write a random number (Verification string) to the session
18. Session. removeall ();
19. Session ["chkcode"] = intrandom;
20. // Font name
21. String strfontname = "Arial ";
22. // Font size
23. Int intfontsize = 9;
24. // Image Width
25. Int intwidth = 35;
26. // Image Length
27. Int intheight = 18;
28. // Background color
29. Color bgcolor = colortranslator. fromhtml ("#" + request. querystring ["colorb"]);
30. // Foreground color
31. Color forecolor = colortranslator. fromhtml ("#" + request. querystring ["colgrading"]);
32. // Generate a font
33. Font forfont = new font (strfontname, intfontsize, fontstyle. Bold );
34. // Generate an image
35. Bitmap newbitmap = new Bitmap (intwidth, intheight, pixelformat. format32bppargb );
36. Graphics G = graphics. fromimage (newbitmap );
37. // Define the same size of a square box as the word slice
38. Rectangle newrect = new rectangle (0, 0, intwidth, intheight );
39. // Apply the background color
40. G. fillrectangle (New solidbrush (bgcolor), newrect );
41. // Write
42. G. drawstring (intrandom. tostring (), forfont, new solidbrush (forecolor), 2, 2 );
43. Memorystream mstream = new memorystream ();
44. // Save to memorystream
45. Newbitmap. Save (mstream, imageformat. GIF );
46. G. Dispose ();
47. Newbitmap. Dispose ();
48. // Send
49. Response. clearcontent ();
50. Response. contenttype = "image/GIF ";
51. Response. binarywrite (mstream. toarray ());
52. Response. End ();
53. }
54. }

2. Call Method

1. <Asp: Image id = "image1" runat = "server" imageurl = "chkcode. aspx? Colgrading = ff0000 & colorb = efb3ff "/>