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Cannot Modify The Result Of An Unboxing Conversion Struct

The final conversion you've shown is a reference conversion - it maintains representational identity, so the values of X and R are both references to the same object. Secondly, do I really have to create a new class with similar content of the struct to get rid of this error? The content you requested has been removed. Any simpler way of modifying just the particular inner element(Oe1)? http://ecoflashapps.com/cannot-modify/cannot-modify-result-unboxing-conversion-c.html

Secondly, do I really have to create a new class with similar content of the struct to get rid of this error? If you care, you might be able to help us solve a little mystery about the edits in your question. DateTime is an example: you can't *change* the "seconds" (for example) of an existing DateTime - you can, however, swap the structure for a different one, created either via a constructor, The first type of element is a class, the other type of element is a struct. http://stackoverflow.com/questions/17280547/why-can-i-not-modify-the-result-of-an-unboxing-conversion

Thursday, October 01, 2009 3:36 PM 1 Sign in to vote Not beautiful, but it should work:for (int i = 0; i < instruments.Count; i++){                VCV oldVCV = (VCV)htVCV[i];                htVCV[i] = NT is an affiliated company to NinjaTrader Brokerage (NTB), which is an NFA registered introducing broker (NFA #0339976). To reach the class members of Osto you need to implement an additional step: Osto o = Shortord[i]; o.os2 = ExitShortStop(...); Since we are dealing with class references, the modifications in P: n/a Hkan Johansson error CS0445: Cannot modify the result of an unboxing conversion I'm quite new to C# and can't really see how to get rid of the above error.

A very simple modification in my code. So correct comments would be int x = (int)2.5; //casting with conversion object a=x; //casting with boxing int Y=(int)a; //casting with unboxing Random r=new Random(); object X=r; Random R=(Random)X; //casting without However, in the case of the struct type element, C# won't allow it. From the context of your reply I suppose it means that value type variables such as int and struct are inherently mutable, i.e.

Learning resources Microsoft Virtual Academy Channel 9 MSDN Magazine Community Forums Blogs Codeplex Support Self support Programs BizSpark (for startups) Microsoft Imagine (for students) United States (English) Newsletter Privacy & cookies Firstly, having a mutable struct is generally a bad idea - it's likely to bite you sooner or later. First it unboxes to int, and then converts to long Another interesting bit is that a nullable value-type gets boxed as it's non nullable type, and can be unboxed as both https://bytes.com/topic/c-sharp/answers/665395-cannot-modify-result-unboxing-conversion Point^) and treating (some) classes as value types (e.g.

Struct Osto contains IOrders like Oe1, Oe2, Os1, Os2 and Ol1 along with other data types. That's where the copy comes in. The first type of element is a class, the other type of element is a struct. Example: int a = (int)byteValue; Boxing and unboxing comes into play when you're casting a value type to and from a reference type, typically object, or one of the interfaces the

If the value type were immutable, you couldn't assign to a simple field in the first place, and therefor had to assign a whole value, (wich now still is possible.) Christof https://msdn.microsoft.com/en-us/library/1zd0a13x.aspx You still need to change the value in the ArrayList manually, but you don't get into diffculties working out the different situations and whether something's made a copy or not. Compiler Error CS0445 Visual Studio 2015 Other Versions Visual Studio 2013 Visual Studio 2012 Visual Studio 2010 Visual Studio 2008 Visual Studio 2005  Updated: July 20, 2015Cannot modify the result of At delivery time, client criticises the lack of some features that weren't written on my quote.

Marked as answer by HarryBedi Thursday, October 01, 2009 2:25 PM Thursday, October 01, 2009 2:01 PM 0 Sign in to vote There's a good reason it doesn't let you do http://ecoflashapps.com/cannot-modify/cannot-modify-the-result-of-an-unboxing-conversion-net.html int myInt=1; object x=myInt;//box int unbox1=(int)x;//successful unbox int? I think your late initialization makes more sense for my routine and I have two more options . Let's assume that "someValueType" is a struct, which also implements IDisposable: IDisposable disp = (IDisposable)someValueType; // boxed Casting a reference type, can do something else as well.

As an example, a Form is mutable: you can change the caption (Text) etc after it has been created. Developer does not see priority in git Development Workflow being followed How to import someone else's toolbox? Marked as answer by HarryBedi Thursday, October 01, 2009 3:46 PM Thursday, October 01, 2009 3:41 PM 0 Sign in to vote Yes I agree - i think i will be http://ecoflashapps.com/cannot-modify/cannot-modify-the-result-of-an-unboxing-conversion-c.html The views and opinions expressed in this forum are those of the authors and do not necessarily reflect the official policy or position of NT or NTB. -- Fixed Width ----

And there, boxing does imply copying (§ 4.3.2): “An unboxing operation […] consists of […] copying the value out of the instance.” –svick Jun 24 '13 at 17:20 | show 4 Unboxing it does create a copy, even if you don't assign it to a variable. –Servy Jun 24 '13 at 17:12 4 @colinfang If you want to follow the rules unbox2=(int?)x;//successful unbox long unbox3=(long)x;//error can't unbox int to long long unbox4=(long)(int)x;//works.

Many (the majority of, but sadly [IMO] not all) structs are immutable.

You could try using a Dictionary instead (which is pretty much a strongly-typed hash table). share|improve this answer answered Jan 19 '11 at 11:48 Jon Skeet 905k48965727494 Thank you. It was very useful! I am using a ArrayList of struc Osto.

You have explained every thing I need to know about List and Class. It's analogue to Location.X = 10. Another way is using a temp variable. navigate here What that operator does, is up to the author of that operator.

Regards Carl Johansson Jun 20 '07 #4 P: n/a Carl Johansson Dear Jon! When you fetch the element from the ArrayList and unbox it, the value you've got back is now completely independent of the value in the ArrayList - it's just a copy. These are public struct sCandle { public double Close; } public struct VCV { public double STDev; public double Mean; public int Obs; public int df; } My hashtables are created What is the total sum of the cardinalities of all subsets of a set?