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. c# var

c# var

Scheduled Pinned Locked Moved The Lounge
questioncsharplounge
60 Posts 37 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.
  • S Slacker007

    it is good for a lot of applications but can be missused very easily. it's main purpose is code readability.

    MyMostExcellentBaseClassOfAllClassesInTheWholeWorld myClass = new MyMostExcellentBaseClassOfAllClassesInTheWholeWorld();

    or

    var myClass = new MyMostExcellentBaseClassOfAllClassesInTheWholeWorld();

    It is really good when working with Linq, etc. as well.

    F Offline
    F Offline
    F ES Sitecore
    wrote on last edited by
    #26

    Slacker007 wrote:

    it's main purpose is code readability.

    Its main purpose is actually anonymous types.

    S 1 Reply Last reply
    0
    • F F ES Sitecore

      Slacker007 wrote:

      it's main purpose is code readability.

      Its main purpose is actually anonymous types.

      S Offline
      S Offline
      Slacker007
      wrote on last edited by
      #27

      I guess it could be used for both, but most people use it for implicit, which by nature adds to code readability for most. Edit: implicit and anonymous. but when I use it, I am not thinking "anonymous" or "Implicit" etc, I am thinking code readability. var - C# Reference | Microsoft Docs[^] c# - Implicitly Typed vs Anonymous Type - Stack Overflow[^]

      1 Reply Last reply
      0
      • R rnbergren

        is it lazy. Sure is. Does it work. Unfortunately yes and Fortunately yes. AS mentioned already when refactoring code and say a variable changes from int to long or even to a string it makes sure the code continues to work. I don't like it. but that does not mean I have never used it. I have and I hate myself for it. But I remember one time I had to write a bit of code. The co-workers insisted that the variable would always be an integer. ALWAYS they said. having some experience I knew probably gonna change. About a year later system requirements changed. I had used var and the code still worked. sooooooo tldr; lazy yes, flexible yes, hate myself yes.

        To err is human to really mess up you need a computer

        OriginalGriffO Offline
        OriginalGriffO Offline
        OriginalGriff
        wrote on last edited by
        #28

        The problem with that is that you are working to what should have been a breaking change. And that's important, because if you were assuming int division as a result of the original type spec for example, then a breaking change means you know it's just failed and can adapt to it. var in that case means you don't know, and output can be subtly wrong and unnoticed until it's a real problem. I'd say var should be there for temporary storage of Linq results, and nowhere else ...

        "I have no idea what I did, but I'm taking full credit for it." - ThisOldTony AntiTwitter: @DalekDave is now a follower!

        "I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
        "Common sense is so rare these days, it should be classified as a super power" - Random T-shirt

        pkfoxP 1 Reply Last reply
        0
        • Z ZurdoDev

          What is the love affair with var? I see sample code where they do something like

          var url = "http://someapi";

          This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

          Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

          P Offline
          P Offline
          PIEBALDconsult
          wrote on last edited by
          #29

          That's just pure laziness.

          1 Reply Last reply
          0
          • M Marc Clifton

            ZurdoDev wrote:

            This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

            I felt the same way initially, and I agree, for something simple like a native type, I rarely use var. However: var complicatedDictionary = new Dictionary>(); and worse, I like definitely like it.

            Latest Articles:
            Abusing Extension Methods, Null Continuation, and Null Coalescence Operators

            D Offline
            D Offline
            dandy72
            wrote on last edited by
            #30

            +1 For native types, I don't see the point in using var. I also subscribe to the idea of using: var x = new SomeMoreComplexType(); I don't mind: var x = SomeFunction(); ...if *I* don't particularly case about the type returned, for example, if I only use it to forward to some other function and I'm not looking at any of its members myself.

            1 Reply Last reply
            0
            • Z ZurdoDev

              What is the love affair with var? I see sample code where they do something like

              var url = "http://someapi";

              This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

              Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

              M Offline
              M Offline
              MadMyche
              wrote on last edited by
              #31

              ZurdoDev wrote:

              var url = "http://someapi";

              Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

              Is it a string? Could it be a URI[^]

              Uri siteUri = new Uri("http://www.contoso.com/");

              Director of Transmogrification Services Shinobi of Query Language Master of Yoda Conditional

              Z 1 Reply Last reply
              0
              • M MadMyche

                ZurdoDev wrote:

                var url = "http://someapi";

                Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

                Is it a string? Could it be a URI[^]

                Uri siteUri = new Uri("http://www.contoso.com/");

                Director of Transmogrification Services Shinobi of Query Language Master of Yoda Conditional

                Z Offline
                Z Offline
                ZurdoDev
                wrote on last edited by
                #32

                Yes, it was a string.

                Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                M 1 Reply Last reply
                0
                • Greg UtasG Greg Utas

                  I use auto, the C++ equivalent, whenever it will deduce the correct type. - It forces you to initialize the variable. - If the variable is initialized by calling a function, and that function's return type changes, the code might not even be affected. - Some type names are long or complicated, and I hate spilling lines. Some argue that it makes the code harder to understand because the reader has to figure out the type. My counterargument is that the reader doesn't understand how the code fits into the system if this is the case.

                  Robust Services Core | Software Techniques for Lemmings | Articles

                  M Offline
                  M Offline
                  Mircea Neacsu
                  wrote on last edited by
                  #33

                  You are going on a dangerous path. It leads you to the days when an insignificant dot was significant:

                  auto i = 2;
                  auto j = 3;
                  auto k = i/j;
                  auto f = 2./j;
                  // f != k
                  // any similarity with FORTRAN is intentional

                  Besides "auto" has four letters and "int" has three; it's not energy efficient :)

                  Mircea

                  Greg UtasG 1 Reply Last reply
                  0
                  • M Mircea Neacsu

                    You are going on a dangerous path. It leads you to the days when an insignificant dot was significant:

                    auto i = 2;
                    auto j = 3;
                    auto k = i/j;
                    auto f = 2./j;
                    // f != k
                    // any similarity with FORTRAN is intentional

                    Besides "auto" has four letters and "int" has three; it's not energy efficient :)

                    Mircea

                    Greg UtasG Offline
                    Greg UtasG Offline
                    Greg Utas
                    wrote on last edited by
                    #34

                    Not very dangerous unless one ignores compiler warnings. Then again, I don't use floating point very often. The main one I have to watch for is

                    for(auto i = 0...

                    which makes i an int when what might actually be called for is a size_t.

                    Robust Services Core | Software Techniques for Lemmings | Articles

                    <p><a href="https://github.com/GregUtas/robust-services-core/blob/master/README.md">Robust Services Core</a>
                    <em>The fox knows many things, but the hedgehog knows one big thing.</em></p>

                    1 Reply Last reply
                    0
                    • Z ZurdoDev

                      Yes, it was a string.

                      Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                      M Offline
                      M Offline
                      MadMyche
                      wrote on last edited by
                      #35

                      But what if you meant it as a URI? I think SQL would call this ambiguous

                      Director of Transmogrification Services Shinobi of Query Language Master of Yoda Conditional

                      Z 1 Reply Last reply
                      0
                      • M MadMyche

                        But what if you meant it as a URI? I think SQL would call this ambiguous

                        Director of Transmogrification Services Shinobi of Query Language Master of Yoda Conditional

                        Z Offline
                        Z Offline
                        ZurdoDev
                        wrote on last edited by
                        #36

                        MadMyche wrote:

                        But what if you meant it as a URI?

                        Then you do new Uri(string);

                        Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                        1 Reply Last reply
                        0
                        • Z ZurdoDev

                          What is the love affair with var? I see sample code where they do something like

                          var url = "http://someapi";

                          This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

                          Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                          M Offline
                          M Offline
                          Mycroft Holmes
                          wrote on last edited by
                          #37

                          When I moved from VB (where purists dump on var from a great height) to c# where explicit types were mandatory I lost all faith in var, it became the one thing in VB that I loathed. Now that it has phoenixed in c# I refuse to use it. As for var content changing type and not having to refactor, what a croc of shit, you should HAVE to refactor if you change type or at least check your usage of the variable.

                          Never underestimate the power of human stupidity - RAH I'm old. I know stuff - JSOP

                          Sander RosselS 1 Reply Last reply
                          0
                          • OriginalGriffO OriginalGriff

                            I'd actually prefer it is you could do this:

                            Dictionary> complicatedDictionary = new *();

                            To me, that would be a more natural way of showing what the type of complicatedDictionary actually is. As it is, I find var is mainly over used by the lazy-and-don't-care script kiddies ...

                            "I have no idea what I did, but I'm taking full credit for it." - ThisOldTony AntiTwitter: @DalekDave is now a follower!

                            pkfoxP Offline
                            pkfoxP Offline
                            pkfox
                            wrote on last edited by
                            #38

                            Yes I agree

                            "We can't stop here - this is bat country" - Hunter S Thompson - RIP

                            1 Reply Last reply
                            0
                            • OriginalGriffO OriginalGriff

                              The problem with that is that you are working to what should have been a breaking change. And that's important, because if you were assuming int division as a result of the original type spec for example, then a breaking change means you know it's just failed and can adapt to it. var in that case means you don't know, and output can be subtly wrong and unnoticed until it's a real problem. I'd say var should be there for temporary storage of Linq results, and nowhere else ...

                              "I have no idea what I did, but I'm taking full credit for it." - ThisOldTony AntiTwitter: @DalekDave is now a follower!

                              pkfoxP Offline
                              pkfoxP Offline
                              pkfox
                              wrote on last edited by
                              #39

                              :thumbsup::thumbsup::thumbsup:

                              "We can't stop here - this is bat country" - Hunter S Thompson - RIP

                              1 Reply Last reply
                              0
                              • Z ZurdoDev

                                What is the love affair with var? I see sample code where they do something like

                                var url = "http://someapi";

                                This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

                                Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                                Sander RosselS Offline
                                Sander RosselS Offline
                                Sander Rossel
                                wrote on last edited by
                                #40

                                I use var almost exclusively these days. I started out using it sometimes, but then I started using it more and more. To me, it just seems nice to have all my vars lined up nicely :D Some people thing the var keyword isn't strongly typed, but it is (we have dynamic for that). It's not like JavaScript's var keyword. It's only absolutely necessary to use var when working with anonymous types (still strongly typed!).

                                Best, Sander sanderrossel.com Migrating Applications to the Cloud with Azure arrgh.js - Bringing LINQ to JavaScript Object-Oriented Programming in C# Succinctly

                                1 Reply Last reply
                                0
                                • M Mycroft Holmes

                                  When I moved from VB (where purists dump on var from a great height) to c# where explicit types were mandatory I lost all faith in var, it became the one thing in VB that I loathed. Now that it has phoenixed in c# I refuse to use it. As for var content changing type and not having to refactor, what a croc of shit, you should HAVE to refactor if you change type or at least check your usage of the variable.

                                  Never underestimate the power of human stupidity - RAH I'm old. I know stuff - JSOP

                                  Sander RosselS Offline
                                  Sander RosselS Offline
                                  Sander Rossel
                                  wrote on last edited by
                                  #41

                                  VB doesn't have var? :confused: The equivalent would be:

                                  Dim something = "my string"

                                  Which looks fine to me and is still strongly typed, unless Options Strict is Off.

                                  Mycroft Holmes wrote:

                                  As for var content changing type and not having to refactor

                                  Using var is strongly typed so I don't really get what you're saying. Are you thinking of dynamic or Option Strict Off (which luckily DOESN'T have an equivalent in C# X| )?

                                  Best, Sander sanderrossel.com Migrating Applications to the Cloud with Azure arrgh.js - Bringing LINQ to JavaScript Object-Oriented Programming in C# Succinctly

                                  M 1 Reply Last reply
                                  0
                                  • G GuyThiebaut

                                    The advantage of var is if "http://someapi" was a variable or class instance instead of a string literal and you changed its type, you would not then need to refactor the code elsewhere. In your example it's just a case of habit probably, however it's obvious from what is on the right that it's a string. It can sometimes make it harder to debug issues as jumping to the class definition might not always be supported in the IDE you use to debug the var url value with or have to wait for the IDE to resolve the type that the var is. That's my take on var...

                                    “That which can be asserted without evidence, can be dismissed without evidence.”

                                    ― Christopher Hitchens

                                    B Offline
                                    B Offline
                                    BillWoodruff
                                    wrote on last edited by
                                    #42

                                    GuyThiebaut wrote:

                                    The advantage of var is if "http://someapi" was a variable or class instance instead of a string literal and you changed its type, you would not then need to refactor the code elsewhere.

                                    "O, that way madness lies; let me shun that!" (King Lear)

                                    «One day it will have to be officially admitted that what we have christened reality is an even greater illusion than the world of dreams.» Salvador Dali

                                    G 1 Reply Last reply
                                    0
                                    • M Marc Clifton

                                      OriginalGriff wrote:

                                      that would be a more natural way of showing what the type

                                      Yup. And as I replied on the Insider News, what I really want is: var foo = new(); In most cases, the compiler should be able to figure out what foo is by inspecting its usage in the code! :laugh:

                                      Latest Articles:
                                      Abusing Extension Methods, Null Continuation, and Null Coalescence Operators

                                      B Offline
                                      B Offline
                                      BillWoodruff
                                      wrote on last edited by
                                      #43

                                      Marc Clifton wrote:

                                      In most cases, the compiler should be able to figure out what foo is by inspecting its usage in the code!

                                      If you turn the compiler into a psychic, be prepared for bad news :wtf:

                                      «One day it will have to be officially admitted that what we have christened reality is an even greater illusion than the world of dreams.» Salvador Dali

                                      1 Reply Last reply
                                      0
                                      • B BillWoodruff

                                        GuyThiebaut wrote:

                                        The advantage of var is if "http://someapi" was a variable or class instance instead of a string literal and you changed its type, you would not then need to refactor the code elsewhere.

                                        "O, that way madness lies; let me shun that!" (King Lear)

                                        «One day it will have to be officially admitted that what we have christened reality is an even greater illusion than the world of dreams.» Salvador Dali

                                        G Offline
                                        G Offline
                                        GuyThiebaut
                                        wrote on last edited by
                                        #44

                                        Tell me about it, I have been coding in Kotlin for an Android application and in Kotlin pretty much every type is inferred. So the code is peppered with it when referring to a property and it can be pretty much anything.

                                        “That which can be asserted without evidence, can be dismissed without evidence.”

                                        ― Christopher Hitchens

                                        1 Reply Last reply
                                        0
                                        • Z ZurdoDev

                                          What is the love affair with var? I see sample code where they do something like

                                          var url = "http://someapi";

                                          This feels lazy to me but I am open minded and am curious if I am missing something. Is there some benefit to declaring most things var instead of what they actually are? In the case above, a string.

                                          Social Media - A platform that makes it easier for the crazies to find each other. Everyone is born right handed. Only the strongest overcome it. Fight for left-handed rights and hand equality.

                                          S Offline
                                          S Offline
                                          Steve Naidamast
                                          wrote on last edited by
                                          #45

                                          The C# "var" construct and other such constructs in both C# and VB.NET are merely short-cuts or the usage of system defaults. This makes for very ambiguous code over the length of an application's development. This is why I don't even use the generic list-type and still use array-lists instead. Despite the slight performance decreases (which most will not notice since such constructs often do not contain thousands of objects or items in general), having easy to read strongly typed code makes my applications much more easily maintainable.

                                          Steve Naidamast Sr. Software Engineer Black Falcon Software, Inc. blackfalconsoftware@outlook.com

                                          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