Disassemble code in Visual Studio instead of ILDASM disassembler

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Disassemble code in Visual Studio instead of ILDASM disassembler


Most of the times when we want to see the disassembled code we will go for the ILDASM tool and give the mapped path of the dll and see the disassembled code in the tool. Now we have an option for that in Visual Studio itself. Let’s see in this article on how to do this step by step.


Let’s open a console application and make a small application and see how visual studio disassembles the code and shows the output.

Create a console application and place the below code in the main method.



                Console.Write("Please Enter the Year: ");

                int year = int.Parse(Console.ReadLine());

                if ((year % 4 == 0) && (year % 100 != 0) || (year % 400 == 0))


                    Console.WriteLine("The year {0}, is a Leap Year", year);




                    Console.WriteLine("The year {0}, is not a Leap Year", year);



            catch (Exception ex)





Place a break point at the execution end level to see the disassembled code as shown in the below image

Now run the application by pressing F5 from the keyboard or directly press the arrow button in the IDE to start the execution process. It will run the steps and go to the break point as shown below.


Now right click on the code and u can see the option Go To Disassembly as shown in the below image


Finally it will open a new window where you can see the disassembled code as shown in the below image

The output of the disassembled code will be similar to the below

--- C:\Users\karthik\Documents\Visual Studio 2010\Projects\ConAppDisassemble\ConAppDisassemble\Program.cs
00000000  push        ebp
00000001  mov         ebp,esp
00000003  push        edi
00000004  push        esi
00000005  push        ebx
00000006  sub         esp,64h
00000009  mov         esi,ecx
0000000b  lea         edi,[ebp-38h]
0000000e  mov         ecx,0Bh
00000013  xor         eax,eax
00000015  rep stos    dword ptr es:[edi]
00000017  mov         ecx,esi
00000019  xor         eax,eax
0000001b  mov         dword ptr [ebp-1Ch],eax
0000001e  mov         dword ptr [ebp-3Ch],ecx
00000021  cmp         dword ptr ds:[005A14B0h],0
00000028  je          0000002F
0000002a  call        6415370F
0000002f  xor         edx,edx
00000031  mov         dword ptr [ebp-40h],edx
00000034  xor         edx,edx
00000036  mov         dword ptr [ebp-44h],edx
00000039  mov         dword ptr [ebp-48h],0
00000040  nop
00000041  nop
                Console.Write("Please Enter the Year: ");
00000042  mov         ecx,dword ptr ds:[02942088h]
00000048  call        6337B098
0000004d  nop
                int year = int.Parse(Console.ReadLine());
0000004e  call        638F9E40
00000053  mov         dword ptr [ebp-4Ch],eax
00000056  mov         ecx,dword ptr [ebp-4Ch]
00000059  call        632FF19C
0000005e  mov         dword ptr [ebp-50h],eax
00000061  mov         eax,dword ptr [ebp-50h]
00000064  mov         dword ptr [ebp-40h],eax
                if ((year % 4 == 0) && (year % 100 != 0) || (year % 400 == 0))
00000067  mov         eax,dword ptr [ebp-40h]
0000006a  and         eax,80000003h
0000006f  jns         00000076
00000071  dec         eax
00000072  or          eax,0FFFFFFFCh
00000075  inc         eax
00000076  test        eax,eax
00000078  jne         00000089
0000007a  mov         eax,dword ptr [ebp-40h]
0000007d  mov         ecx,64h
00000082  cdq
00000083  idiv        eax,ecx
00000085  test        edx,edx
00000087  jne         000000A2
00000089  nop
0000008a  mov         eax,dword ptr [ebp-40h]
0000008d  mov         ecx,190h
00000092  cdq
00000093  idiv        eax,ecx
00000095  test        edx,edx
00000097  setne       al
0000009a  movzx       eax,al
0000009d  mov         dword ptr [ebp-54h],eax
000000a0  jmp         000000A7
000000a2  xor         edx,edx
000000a4  mov         dword ptr [ebp-54h],edx
000000a7  movzx       eax,byte ptr [ebp-54h]
000000ab  mov         dword ptr [ebp-48h],eax
000000ae  cmp         dword ptr [ebp-48h],0
000000b2  jne         000000EA
000000b4  nop
                    Console.WriteLine("The year {0}, is a Leap Year", year);
000000b5  mov         ecx,638A2978h
000000ba  call        FFE6FBE0
000000bf  mov         dword ptr [ebp-58h],eax
000000c2  mov         eax,dword ptr ds:[0294208Ch]
000000c8  mov         dword ptr [ebp-64h],eax
000000cb  mov         eax,dword ptr [ebp-58h]
000000ce  mov         edx,dword ptr [ebp-40h]
000000d1  mov         dword ptr [eax+4],edx
000000d4  mov         eax,dword ptr [ebp-58h]
000000d7  mov         dword ptr [ebp-68h],eax
000000da  mov         ecx,dword ptr [ebp-64h]
000000dd  mov         edx,dword ptr [ebp-68h]
000000e0  call        6331B090
000000e5  nop
000000e6  nop
000000e7  nop
000000e8  jmp         0000011D
000000ea  nop
                    Console.WriteLine("The year {0}, is not a Leap Year", year);
000000eb  mov         ecx,638A2978h
000000f0  call        FFE6FBE0
000000f5  mov         dword ptr [ebp-58h],eax
000000f8  mov         eax,dword ptr ds:[02942090h]
000000fe  mov         dword ptr [ebp-6Ch],eax
00000101  mov         eax,dword ptr [ebp-58h]
00000104  mov         edx,dword ptr [ebp-40h]
00000107  mov         dword ptr [eax+4],edx
0000010a  mov         eax,dword ptr [ebp-58h]
0000010d  mov         dword ptr [ebp-70h],eax
00000110  mov         ecx,dword ptr [ebp-6Ch]
00000113  mov         edx,dword ptr [ebp-70h]
00000116  call        6331B090
0000011b  nop
0000011c  nop
0000011d  nop
0000011e  nop
0000011f  jmp         0000014A
            catch (Exception ex)
00000121  mov         dword ptr [ebp-5Ch],eax
00000124  mov         eax,dword ptr [ebp-5Ch]
00000127  mov         dword ptr [ebp-44h],eax
0000012a  nop
0000012b  mov         ecx,dword ptr [ebp-44h]
0000012e  mov         eax,dword ptr [ecx]
00000130  mov         eax,dword ptr [eax+28h]
00000133  call        dword ptr [eax+10h]
00000136  mov         dword ptr [ebp-60h],eax
00000139  mov         ecx,dword ptr [ebp-60h]
0000013c  call        63324C6C
00000141  nop
00000142  nop
00000143  call        63E9FE98
00000148  jmp         0000014A
0000014a  nop
0000014b  call        638F9E40
00000150  nop
00000151  nop
00000152  lea         esp,[ebp-0Ch]
00000155  pop         ebx
00000156  pop         esi
00000157  pop         edi
00000158  pop         ebp
00000159  ret


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About the Author

Full Name: Karthikeyan Anbarasan
Member Level: Silver
Member Status: Member,Moderator,Microsoft_MVP,MVP
Member Since: 1/2/2011 3:00:14 AM
Country: India
Thanks Karthik www.f5Debug.net
www.f5Debug.net Around 5 years of experience in Microsoft technologies like ASP.Net, VB.Net, C#.net, SQL server, Biztalk Server, WCF, WPF, SSIS, SSRS, SSAS, AJAX and working as Senior Analyst in a US based MNC.

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Comments or Responses

Posted by: Naimishforu on: 2/8/2011 | Points: 25
Hi....In which version this will be shown??

Cause I'm using VS 2010 Ultimate but the option is not coming when I right click :(

Posted by: Karthikanbarasan on: 2/8/2011 | Points: 25
Its available in 2005/2008 and also in 2010 versions of .net

You can see my screen shots for examples
Posted by: Andyclap on: 2/11/2011 | Points: 25
Apples and oranges. This is the post-jit x86 you're reading, not the IL. Not so relevant for a c# programmer, unless you're interested in the workings of your particular runtime's jit compiler.
Posted by: Akiii on: 5/15/2011 | Points: 25
nice one....


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