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. Other Discussions
  3. The Weird and The Wonderful
  4. // Do not remove this try catch block.

// Do not remove this try catch block.

Scheduled Pinned Locked Moved The Weird and The Wonderful
questioncomhelptutorial
22 Posts 14 Posters 0 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.
  • K kristopher baker

    My guess is that either "filters" isn't instantiated or is getting instantiated at the same time that it is being called. What is happening when "IsEmpty" is called? It might be trying to kick something off when it is called.

    M Offline
    M Offline
    Middle Manager
    wrote on last edited by
    #12

    I second that request. Can we be shown the IsEmpty code please? Can't be too many company secrets hidden in there... god, please say there isn't! :omg:

    U Y 2 Replies Last reply
    0
    • Y Yusuf

      try
      {
      Filtering = !filters.IsEmpty;
      }
      catch(Exception ex)
      {
      // Do not remove this try catch block. For some reason this always throws Null reference exception but then works.
      }
      finally
      {
      Filtering = !filters.IsEmpty;
      }

      Oh My eyes :wtf:

      Yusuf May I help you?

      A Offline
      A Offline
      agolddog
      wrote on last edited by
      #13

      Outside of that... Who knows the context, but I'm going to guess that filters is a private member property, and Filtering is exposed. Why wouldn't someone just make Filtering a public, get-only convenience property then, rather than setting some piece of data, where we now have to maintain two things?

      1 Reply Last reply
      0
      • P Plamen Dragiyski

        I think he might not know what Multi-Threaded Programming is.

        B Offline
        B Offline
        Bernhard Hiller
        wrote on last edited by
        #14

        Exactly. But somewhere he read something about lazy initialization, and somewhere else he saw a Task.Run, understood neither of them, and ... Welcome to the wonderful world of code monkeys who've used every programming concept during their career. :^)

        1 Reply Last reply
        0
        • M Middle Manager

          I second that request. Can we be shown the IsEmpty code please? Can't be too many company secrets hidden in there... god, please say there isn't! :omg:

          U Offline
          U Offline
          User 11277767
          wrote on last edited by
          #15

          public bool IsEmpty
          {
          get {
          try {
          return _filters.IsEmpty();
          }
          catch (NullReferenceException e)
          {
          InstantiateFilters();
          throw new NullReferenceException("Try it again now please.");
          }
          }
          }

          K 1 Reply Last reply
          0
          • Y Yusuf

            try
            {
            Filtering = !filters.IsEmpty;
            }
            catch(Exception ex)
            {
            // Do not remove this try catch block. For some reason this always throws Null reference exception but then works.
            }
            finally
            {
            Filtering = !filters.IsEmpty;
            }

            Oh My eyes :wtf:

            Yusuf May I help you?

            D Offline
            D Offline
            Daniel R Przybylski
            wrote on last edited by
            #16

            Are You A Code Poet? - I'm silently reviewing your code T-Shirt | Teespring[^]

            1 Reply Last reply
            0
            • Y Yusuf

              try
              {
              Filtering = !filters.IsEmpty;
              }
              catch(Exception ex)
              {
              // Do not remove this try catch block. For some reason this always throws Null reference exception but then works.
              }
              finally
              {
              Filtering = !filters.IsEmpty;
              }

              Oh My eyes :wtf:

              Yusuf May I help you?

              L Offline
              L Offline
              Leng Vang
              wrote on last edited by
              #17

              Zombie coder?

              1 Reply Last reply
              0
              • L Lost User

                Hmmm, I can infer from this snippet that the filters variable is most likely a CString[^] member variable which is being modified/accessed by multiple threads. Am I right? :) Best Wishes, -David Delaune

                Y Offline
                Y Offline
                Yusuf
                wrote on last edited by
                #18

                Nope. filter is ICollectionView [^](https://msdn.microsoft.com/en-us/library/system.componentmodel.icollectionview(v=vs.110).aspx) type. It is possible it could be null.

                Yusuf May I help you?

                1 Reply Last reply
                0
                • B Bernhard Hiller

                  I am trying to figure out how that can work. What about

                  private Something _filters;
                  private Something filters
                  {
                  get
                  {
                  if (_filters == null)
                  {
                  Task.Run(() => CreateFilters());
                  }
                  return _filters;
                  }
                  }
                  private void CreateFilters()
                  {
                  // somehow instantiates a Something and sets the _filters member
                  }

                  That could cause such a strange behavior, couldn't it? :-D

                  Y Offline
                  Y Offline
                  Yusuf
                  wrote on last edited by
                  #19

                  var filters = Grid.RecordManager.FilteredInDataItems;

                  it is using 3rd party grid control. It returns ICollectionView [^](https://msdn.microsoft.com/en-us/library/system.componentmodel.icollectionview(v=vs.110).aspx)

                  Yusuf May I help you?

                  1 Reply Last reply
                  0
                  • M Middle Manager

                    I second that request. Can we be shown the IsEmpty code please? Can't be too many company secrets hidden in there... god, please say there isn't! :omg:

                    Y Offline
                    Y Offline
                    Yusuf
                    wrote on last edited by
                    #20

                    bool IsEmpty { get; }

                    Member of System.ComponentModel.ICollectionView

                    Yusuf May I help you?

                    1 Reply Last reply
                    0
                    • U User 11277767

                      public bool IsEmpty
                      {
                      get {
                      try {
                      return _filters.IsEmpty();
                      }
                      catch (NullReferenceException e)
                      {
                      InstantiateFilters();
                      throw new NullReferenceException("Try it again now please.");
                      }
                      }
                      }

                      K Offline
                      K Offline
                      kristopher baker
                      wrote on last edited by
                      #21

                      That tells you everything. You're variously trying to call an IsEmpty() method on a null _filters object. The exception is caught, InstantiateFilters() then fills up your filters variable from your calling code. The next time around in the finally it calls on the IsEmpty property again but this time _filters has been instantiated and the 'try' passes without a problem.

                      U 1 Reply Last reply
                      0
                      • K kristopher baker

                        That tells you everything. You're variously trying to call an IsEmpty() method on a null _filters object. The exception is caught, InstantiateFilters() then fills up your filters variable from your calling code. The next time around in the finally it calls on the IsEmpty property again but this time _filters has been instantiated and the 'try' passes without a problem.

                        U Offline
                        U Offline
                        User 11277767
                        wrote on last edited by
                        #22

                        I'm not the OP so I have no knowledge of the actual code. That was just a stupid joke on my part.

                        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