Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
Code Project
  1. Home
  2. The Lounge
  3. how hard to rewrite a legacy software from C++ to C# in WinForm?

how hard to rewrite a legacy software from C++ to C# in WinForm?

Scheduled Pinned Locked Moved The Lounge
csharpc++question
26 Posts 18 Posters 2 Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • H honey the codewitch

    It varies widely depending on the project. For user interface stuff (at least assuming windows) if you were using like, MFC before, you're basically going to need to rewrite that part using the original code as a reference. For algorithmic stuff it depends. If you're doing pointer ops all over the place that will be difficult to port as you need to change it to indexing into arrays (typically). Otherwise, if you're using things like vector and map they have direct corollaries in C# so that kind of thing is easier. Just remember structs are on the stack and classes are on the heap in C#. That has a lot of different ramifications, such as changing how they are passed to functions (byval instead of byref). Be careful when porting that kind of thing from C++ which makes little distinction between classes and structs.

    Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

    Richard Andrew x64R Offline
    Richard Andrew x64R Offline
    Richard Andrew x64
    wrote on last edited by
    #5

    Out of curiosity, is an enum a class or struct?

    The difficult we do right away... ...the impossible takes slightly longer.

    H 1 Reply Last reply
    0
    • Richard Andrew x64R Richard Andrew x64

      Out of curiosity, is an enum a class or struct?

      The difficult we do right away... ...the impossible takes slightly longer.

      H Offline
      H Offline
      honey the codewitch
      wrote on last edited by
      #6

      In C and C++ it doesn't really matter. In fact it's compiled into constant nothings basically (removed). In C# it's a ValueType which makes it closer to a struct than a class in terms of how it behaves - stack vs heap, etc.

      Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

      S 1 Reply Last reply
      0
      • S Southmountain

        I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

        diligent hands rule....

        R Offline
        R Offline
        RedDk
        wrote on last edited by
        #7

        It's easy. Start a new project in the target language of your choice. Copy the bare minimum from the source language, paste it in the new language target husk, and attempt to compile. You'll get tons of errors and warnings. Pick through them and eliminate them one-by-one. Obviously there's a lot of personal experience in "attempting" to do anything using a compiler and a linker. Done this, have I. Learned much have I.

        Richard Andrew x64R O J 3 Replies Last reply
        0
        • R RedDk

          It's easy. Start a new project in the target language of your choice. Copy the bare minimum from the source language, paste it in the new language target husk, and attempt to compile. You'll get tons of errors and warnings. Pick through them and eliminate them one-by-one. Obviously there's a lot of personal experience in "attempting" to do anything using a compiler and a linker. Done this, have I. Learned much have I.

          Richard Andrew x64R Offline
          Richard Andrew x64R Offline
          Richard Andrew x64
          wrote on last edited by
          #8

          RedDk wrote:

          You'll get tons of errors and warnings. Pick through them an eliminate them one-by-one.

          It's hard to tell if that's sage advice or sarcasm.

          The difficult we do right away... ...the impossible takes slightly longer.

          P 1 Reply Last reply
          0
          • Richard Andrew x64R Richard Andrew x64

            RedDk wrote:

            You'll get tons of errors and warnings. Pick through them an eliminate them one-by-one.

            It's hard to tell if that's sage advice or sarcasm.

            The difficult we do right away... ...the impossible takes slightly longer.

            P Offline
            P Offline
            PIEBALDconsult
            wrote on last edited by
            #9

            It sounds like the advice to start with a block of stone and remove the parts which don't look like an elephant.

            1 Reply Last reply
            0
            • K Kenneth Haugland

              MFC to WPF or what? I did some conversions from C++ to C# for a complex math problem. That was pretty straight-forward since the finished C# code was not that different from C++ once you got into it.

              S Offline
              S Offline
              Southmountain
              wrote on last edited by
              #10

              WinForm in my mind.

              diligent hands rule....

              1 Reply Last reply
              0
              • J Jo_vb net

                Don't fear the reaper... ... just start re-writing the code. For smaller parts you can use https://www.codeconvert.ai/c++-to-csharp-converter[^] But you have to revise this converted code anyway.

                S Offline
                S Offline
                Southmountain
                wrote on last edited by
                #11

                :rose::rose::rose:

                diligent hands rule....

                1 Reply Last reply
                0
                • H honey the codewitch

                  In C and C++ it doesn't really matter. In fact it's compiled into constant nothings basically (removed). In C# it's a ValueType which makes it closer to a struct than a class in terms of how it behaves - stack vs heap, etc.

                  Check out my IoT graphics library here: https://honeythecodewitch.com/gfx And my IoT UI/User Experience library here: https://honeythecodewitch.com/uix

                  S Offline
                  S Offline
                  Southmountain
                  wrote on last edited by
                  #12

                  :thumbsup:

                  diligent hands rule....

                  1 Reply Last reply
                  0
                  • R RedDk

                    It's easy. Start a new project in the target language of your choice. Copy the bare minimum from the source language, paste it in the new language target husk, and attempt to compile. You'll get tons of errors and warnings. Pick through them and eliminate them one-by-one. Obviously there's a lot of personal experience in "attempting" to do anything using a compiler and a linker. Done this, have I. Learned much have I.

                    O Offline
                    O Offline
                    obermd
                    wrote on last edited by
                    #13

                    This is exactly how I converted about 10,000 lines of VB6 code to VB 2005. The biggest changes were file handling and error reporting. To this day I'll occasionally use On Error Resume Next in short Subs and Functions when it's appropriate. Otherwise I use Try/Catch/Finally.

                    R N 2 Replies Last reply
                    0
                    • O obermd

                      This is exactly how I converted about 10,000 lines of VB6 code to VB 2005. The biggest changes were file handling and error reporting. To this day I'll occasionally use On Error Resume Next in short Subs and Functions when it's appropriate. Otherwise I use Try/Catch/Finally.

                      R Offline
                      R Offline
                      RedDk
                      wrote on last edited by
                      #14

                      That's it exactly. Initially posting line-numbered QBASIC code into a C++ project ... I was surprised how little squawking the VS interface returned. I like that "On Error Resume" trick. Next time ...

                      1 Reply Last reply
                      0
                      • O obermd

                        This is exactly how I converted about 10,000 lines of VB6 code to VB 2005. The biggest changes were file handling and error reporting. To this day I'll occasionally use On Error Resume Next in short Subs and Functions when it's appropriate. Otherwise I use Try/Catch/Finally.

                        N Offline
                        N Offline
                        Nelek
                        wrote on last edited by
                        #15

                        obermd wrote:

                        To this day I'll occasionally use On Error Resume Next

                        as long as you put something in between... :rolleyes: ;P :laugh:

                        M.D.V. ;) If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about? Help me to understand what I'm saying, and I'll explain it better to you Rating helpful answers is nice, but saying thanks can be even nicer.

                        O 1 Reply Last reply
                        0
                        • S Southmountain

                          I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                          diligent hands rule....

                          A Offline
                          A Offline
                          Amarnath S
                          wrote on last edited by
                          #16

                          Outsource to someone here (me?).

                          1 Reply Last reply
                          0
                          • S Southmountain

                            I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                            diligent hands rule....

                            B Offline
                            B Offline
                            Bruno van Dooren
                            wrote on last edited by
                            #17

                            Does it 'need' to be C#? Or can you use C++/CLI? Because the latter would be much simpler, in the sense that you can keep your algorithms and the back end stuff in C++, and do the user interface in C++/CLI. Is your user interface in MFC, or WTL or something else? The user interface would have to be re-built from scratch

                            1 Reply Last reply
                            0
                            • S Southmountain

                              I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                              diligent hands rule....

                              G Offline
                              G Offline
                              Gary R Wheeler
                              wrote on last edited by
                              #18

                              You're going to have to rewrite UI code regardless. The one advantage going to WinForms would be correspondence in the UI. WinForms is something of a wrapper around Windows GDI controls for C#, in the same sense that MFC is a wrapper for C++.

                              Software Zen: delete this;

                              1 Reply Last reply
                              0
                              • S Southmountain

                                I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                                diligent hands rule....

                                M Offline
                                M Offline
                                MSBassSinger
                                wrote on last edited by
                                #19

                                In my experience of rewriting from one language into C#, there are a few principles I applied that helped me. 1 - Understand the requirements, architecture, and intent of the original code (which may have to be determined with only the original code at hand). 2 - Understand WHAT the original code is doing. 3 - In the new language (e.g. C#), determine how it best does what the original code did. Just translating code from original to new is a trap. 4 - What does the new language offer (including third party components if you want) that would be useful, that was not used for the original app with the original language? 5 - What new language architecture gives you the lowest total SDLC cost with the best acceptable performance, scalability, and support? Apply these principles and you will avoid a myriad of booby-traps and sloughs of despond.

                                1 Reply Last reply
                                0
                                • S Southmountain

                                  I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                                  diligent hands rule....

                                  B Offline
                                  B Offline
                                  Behzad Sedighzadeh
                                  wrote on last edited by
                                  #20

                                  Isn't it better to use an existing product? Have you looked at ScottPlot ?

                                  Behzad

                                  1 Reply Last reply
                                  0
                                  • S Southmountain

                                    I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                                    diligent hands rule....

                                    O Offline
                                    O Offline
                                    obeobe
                                    wrote on last edited by
                                    #21

                                    I bet ChatGPT can do it.

                                    1 Reply Last reply
                                    0
                                    • S Southmountain

                                      I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                                      diligent hands rule....

                                      T Offline
                                      T Offline
                                      Thornik
                                      wrote on last edited by
                                      #22

                                      Nothing hard. After C++ you'll write C# code like a song.

                                      1 Reply Last reply
                                      0
                                      • R RedDk

                                        It's easy. Start a new project in the target language of your choice. Copy the bare minimum from the source language, paste it in the new language target husk, and attempt to compile. You'll get tons of errors and warnings. Pick through them and eliminate them one-by-one. Obviously there's a lot of personal experience in "attempting" to do anything using a compiler and a linker. Done this, have I. Learned much have I.

                                        J Offline
                                        J Offline
                                        jschell
                                        wrote on last edited by
                                        #23

                                        At least to me the OP suggested that they want to use WinForms and that existing code does not use that. So that is a complete rewrite at least for that part.

                                        1 Reply Last reply
                                        0
                                        • S Southmountain

                                          I have a legacy software to draw very sophisticated charts. but I only need a small piece of these charts. I want to re-write the code charting this small piece of charts. How hard it is to do this? any experience to share?

                                          diligent hands rule....

                                          J Offline
                                          J Offline
                                          jochance
                                          wrote on last edited by
                                          #24

                                          There are good charting controls available off the shelf for WPF, maybe for winforms but just go WPF. If those just won't do, you probably want to look for "using GDI+ from WPF" if you're looking to draw your own charts. If you're really wanting to visualize data in interesting ways, it might not be insane to look into using Unity. Custom rendering with GDI+ is.... hard to get a positive return on investment unless you're a company that sells components for WinForm/WPF.

                                          1 Reply Last reply
                                          0
                                          Reply
                                          • Reply as topic
                                          Log in to reply
                                          • Oldest to Newest
                                          • Newest to Oldest
                                          • Most Votes


                                          • Login

                                          • Don't have an account? Register

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • World
                                          • Users
                                          • Groups