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. General Programming
  3. C#
  4. Dynamically assign values to instance

Dynamically assign values to instance

Scheduled Pinned Locked Moved C#
csharplinqperformancetutorialquestion
20 Posts 5 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.
  • C Calin Tatar

    Basically, you are searching for an alternative to Reflection, right? Calin

    S Offline
    S Offline
    Stevo Z
    wrote on last edited by
    #9

    Kind of. Something that does the job but keeps the speed on same level as direct access.

    zilo

    C 2 Replies Last reply
    0
    • S Stevo Z

      Kind of. Something that does the job but keeps the speed on same level as direct access.

      zilo

      C Offline
      C Offline
      Calin Tatar
      wrote on last edited by
      #10

      I think you could try by using Dynamic Invocation. Calin

      S 1 Reply Last reply
      0
      • C Calin Tatar

        I think you could try by using Dynamic Invocation. Calin

        S Offline
        S Offline
        Stevo Z
        wrote on last edited by
        #11

        Do you suggest to create a method using reflection on the fly:

        void AssingAValue(AClass aInstance, object value)
        {
        aInstance.AValue = value;
        }

        and then just call this method?

        zilo

        C 1 Reply Last reply
        0
        • S Stevo Z

          Do you suggest to create a method using reflection on the fly:

          void AssingAValue(AClass aInstance, object value)
          {
          aInstance.AValue = value;
          }

          and then just call this method?

          zilo

          C Offline
          C Offline
          Calin Tatar
          wrote on last edited by
          #12

          yes, so you can dynamically change the AValue property. Calin

          1 Reply Last reply
          0
          • S Stevo Z

            Yes. I'm loading the class from dll as

            Assembly.LoadFile(string file);

            And I'd like to keep AClass as simple as possible, without any specific code to read or write values into it. It's just a data container.

            zilo

            S Offline
            S Offline
            S Senthil Kumar
            wrote on last edited by
            #13

            Well, LINQ knows the types of data objects at compile time, so there's no similarity there. Without reflection, I guess your best bet is emitting the IL directly[^].

            Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro

            S 1 Reply Last reply
            0
            • S Stevo Z

              Interesting idea, but... It's not only one, there will be many properties like this within AClass. And it needs to be done outside of constructor.

              zilo

              D Offline
              D Offline
              DaveyM69
              wrote on last edited by
              #14

              Maybe extension methods could work. Create an extension method ToAClass for each type, and also pass the AClass instance.

              public static class ExtensionMethods
              {
              static public void SetAClass(this string value, AClass instance)
              {
              instance.AString = value;
              }

              static public void SetAClass(this int value, AClass instance)
              {
                  instance.AInt = value;
              }
              

              }
              public class AClass
              {
              public string AString
              {
              get;
              set;
              }
              public int AInt
              {
              get;
              set;
              }
              }

              AClass aInstance = new AClass();
              "Test string".SetAClass(aInstance);
              123.SetAClass(aInstance);

              Dave
              BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
              Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)

              S 1 Reply Last reply
              0
              • D DaveyM69

                Maybe extension methods could work. Create an extension method ToAClass for each type, and also pass the AClass instance.

                public static class ExtensionMethods
                {
                static public void SetAClass(this string value, AClass instance)
                {
                instance.AString = value;
                }

                static public void SetAClass(this int value, AClass instance)
                {
                    instance.AInt = value;
                }
                

                }
                public class AClass
                {
                public string AString
                {
                get;
                set;
                }
                public int AInt
                {
                get;
                set;
                }
                }

                AClass aInstance = new AClass();
                "Test string".SetAClass(aInstance);
                123.SetAClass(aInstance);

                Dave
                BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
                Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)

                S Offline
                S Offline
                Stevo Z
                wrote on last edited by
                #15

                Anyhow, whether is it extension methods or not, I'll have to create them dynamically using reflection and then just call those methods. I think I have a better idea now, thanks

                zilo

                1 Reply Last reply
                0
                • S S Senthil Kumar

                  Well, LINQ knows the types of data objects at compile time, so there's no similarity there. Without reflection, I guess your best bet is emitting the IL directly[^].

                  Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro

                  S Offline
                  S Offline
                  Stevo Z
                  wrote on last edited by
                  #16

                  It doesn't have to, I'm using those classes to work with linq as well and it's working fine. Thanks for the suggestion, that looks to be the only way to go.

                  zilo

                  S 1 Reply Last reply
                  0
                  • S Stevo Z

                    It doesn't have to, I'm using those classes to work with linq as well and it's working fine. Thanks for the suggestion, that looks to be the only way to go.

                    zilo

                    S Offline
                    S Offline
                    S Senthil Kumar
                    wrote on last edited by
                    #17

                    Zilo(svk) wrote:

                    I'm using those classes to work with linq as well and it's working fine

                    Now I'm curious - can you paste a snippet of code that does that? I can't imagine LINQ working without you specifying the type somewhere (unless it's an anonymous type, of course).

                    Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro

                    S 1 Reply Last reply
                    0
                    • S S Senthil Kumar

                      Zilo(svk) wrote:

                      I'm using those classes to work with linq as well and it's working fine

                      Now I'm curious - can you paste a snippet of code that does that? I can't imagine LINQ working without you specifying the type somewhere (unless it's an anonymous type, of course).

                      Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro

                      S Offline
                      S Offline
                      Stevo Z
                      wrote on last edited by
                      #18

                      I ment the classes are not present withing the same solution or assembly when compiling the code. When working with linq, I'm using strong types. This is a sample of one of the classes:

                      [Table(Name = "Books")]
                      public partial class Book : IDALEntity
                      {
                      private int _BookId;
                      private string _Title;
                      private int _Price;
                      private int _PublisherID;

                          public Book()
                          {   }
                      
                          \[Column(Storage = "\_BookId", AutoSync = AutoSync.OnInsert, DbType = "Int NOT NULL", IsPrimaryKey = true)\]
                          public int BookId
                          {
                              get
                              {
                                  return this.\_BookId;
                              }
                              set
                              {
                                 this.\_BookId = value;                 
                              }
                          }
                      

                      ...
                      }

                      zilo

                      S 1 Reply Last reply
                      0
                      • S Stevo Z

                        I ment the classes are not present withing the same solution or assembly when compiling the code. When working with linq, I'm using strong types. This is a sample of one of the classes:

                        [Table(Name = "Books")]
                        public partial class Book : IDALEntity
                        {
                        private int _BookId;
                        private string _Title;
                        private int _Price;
                        private int _PublisherID;

                            public Book()
                            {   }
                        
                            \[Column(Storage = "\_BookId", AutoSync = AutoSync.OnInsert, DbType = "Int NOT NULL", IsPrimaryKey = true)\]
                            public int BookId
                            {
                                get
                                {
                                    return this.\_BookId;
                                }
                                set
                                {
                                   this.\_BookId = value;                 
                                }
                            }
                        

                        ...
                        }

                        zilo

                        S Offline
                        S Offline
                        S Senthil Kumar
                        wrote on last edited by
                        #19

                        Well, LINQ uses reflection to read the custom attributes you provide for each property, so that it can map them to database columns. I guess they do it just once and then generate dynamic code to do the actual translation from SQL results to object property assignments.

                        Regards Senthil [MVP - Visual C#] _____________________________ My Home Page |My Blog | My Articles | My Flickr | WinMacro

                        1 Reply Last reply
                        0
                        • S Stevo Z

                          Kind of. Something that does the job but keeps the speed on same level as direct access.

                          zilo

                          C Offline
                          C Offline
                          Calin Tatar
                          wrote on last edited by
                          #20

                          Also, you can use TypeDescriptor, and PropertyDescriptor. Calin

                          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