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Type Cannot Be Marshaled As An Unmanaged Structure

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Allocate the buffer and assign values enforcing length checks programatically if you need to do that in the C# code before/after passing to C++. (Using Marshal.Copy(byte[]...) // coming from an ANSI share|improve this answer answered Jun 18 '11 at 23:47 Downvoter 468213 That is! Reference Types: The sizeof operator cannot be used on reference types. Not the answer you're looking for? Check This Out

Application Lifecycle> Running a Business Sales / Marketing Collaboration / Beta Testing Work Issues Design and Architecture ASP.NET JavaScript C / C++ / MFC> ATL / WTL / STL Managed C++/CLI Reply With Quote August 5th, 2010,10:48 AM #2 Grofit View Profile View Forum Posts Member Join Date Nov 2006 Posts 357 Re: Error marshalling pointer to struct with char[] Just a Vent kitchen hood vent to roof turbine vent? error is back The error discussed in this post http://scn.sap.com/thread/1890650 seems to have crept back into SP12.  The following code:Using dbConnection As SqlConnection = GetNewSQLConnection()                    .AddLoginInfo(dbConnection)                    If TypeOf .Report Is IHasParameters http://stackoverflow.com/questions/17879787/marshal-sizeof-throws-argumentexception-on-enums

Marshal.sizeof String

Hello and welcome to PC Review. Mattias -- Mattias Sjögren [MVP] mattias @ mvps.org http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com Please reply only to the newsgroup. It can be used on any value type but will throw an exception at runtime if the value type contains a reference type. That implies the type for which the size is queried should be known at compile time.

The struct is not a generic value type.sizeof should be imagined as a compile-time construct. Search Comments Spacing RelaxedCompactTight Layout NormalOpen TopicsOpen AllThread View Per page 102550 First Prev Next Using CustomMarshaller schlingel00178-Feb-13 0:56 schlingel00178-Feb-13 0:56 When I use a custom marshaller (implements ICustomMarshaller) Is it possible to hand start modern planes? Marshalas(unmanagedtype However,Marshal.SizeOf(SomeStruct) may report to that its char member consumes two bytes (by default) or made to take up one byte (if the StructLayout.CharSet=CharSet.Ansi).

Post your question and get tips & solutions from a community of 418,795 IT Pros & Developers. David "David Browne" wrote in message news:... > > "the openBack" <> wrote in message > news:420aa31f$0$39306$... >> I'm having a problem that I don't quite understand. Browse other questions tagged c# arrays interop struct marshalling or ask your own question. I'm having a problem that I don't quite understand.

Mattias -- Mattias Sjgren [MVP] mattias @ mvps.org http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com Please reply only to the newsgroup. Structlayout Furniture name for waist-high floor-sitting shelf cabinet thing Calculating ...5(5+4(4+3(3+2(2+1(1))))) why does this error keep popping out? Hence the compiler does not allow computing the size of a generic value type. And as per MSDN, the size cannot be computed accurately.

  • Got any clue?
  • ByValArray can only be used with > arrays. > > > > Mattias > That was it, thank you!
  • Are keywords in resolv.conf case sensitive?

Type 'system.string' Cannot Be Marshaled As An Unmanaged Structure

Boss sends a birthday message. https://bytes.com/topic/net/answers/120625-type-can-not-marshaled-unmanaged-structure David Jul 21 '05 #4 P: n/a the openBack Mattias Sjgren wrote: [MarshalAs(UnmanagedType.ByValArray, SizeConst=Kernel.MAX_PATH)]public string szDisplayName; Change ByValArray to ByValTStr. Marshal.sizeof String more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed Marshal.sizeof C# License This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL) Share email twitter facebook linkedin reddit google+ About the Author Vivek

Unlike in C++ (or unmanaged world), computing the size of a type definitely has no such use in C# (managed world). his comment is here more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed I'm using someone else's class: using HANDLE = System.IntPtr; namespace Win32 { // other stuff here public struct SHFILEINFO { public HANDLE hIcon; public int iIcon; public int dwAttributes; [MarshalAs(UnmanagedType.ByValArray, SizeConst=Kernel.MAX_PATH)] CodeGuru Home VC++ / MFC / C++ .NET / C# Visual Basic VB Forums Developer.com Register Help Remember Me? C# Get Size Of Object

I'm using someone >> else's class: >> >> >> using HANDLE = System.IntPtr; >> >> namespace Win32 { >> // other stuff here >> >> public struct SHFILEINFO { >> public Why were pre-election polls and forecast models so wrong about Donald Trump? While this code doesn't throw an exception and size contains 4: public enum MyEnum { V1, V2, V3 } public struct MyStruct { public MyEnum en; } int size = Marshal.SizeOf(typeof(MyStruct)); this contact form Go to top Permalink | Advertise | Privacy | Terms of Use | Mobile Web01 | 2.8.161110.1 | Last Updated 29 Jul 2010 Article Copyright 2010 by Vivek RagunathanEverything else Copyright

However, the sizeof cannot be freely used with user-defined value types (struct) but only if the following conditions are true:- The size of the struct is requested from within an Marshal C# This member is used only with output buffers.            public IntPtr lpNext;           // Reserved.            public IntPtr reserved;         // Reserved.        }How can I get the size of my new struct?  Marshal.SizeOf returns an Is there a way to block a President Elect from entering office?

control ctrl = new control(); byte[] bytes = structtobyte(ctrl); share|improve this answer answered Jun 18 '11 at 23:02 Martin Liversage 65.7k13127185 control cnt;structtobyte(cnt); I`m passing it my edited cnt

How is Anti Aliasing Implemented in Ray Tracing? asked 5 years ago viewed 2865 times active 5 years ago Upcoming Events 2016 Community Moderator Election ends Nov 22 Get the weekly newsletter! We're a friendly computing community, bustling with knowledgeable members to help solve your tech questions. C# Sizeof sizeof(char) is 2 since CLR is an Unicode beast.

Wednesday, October 03, 2007 10:54 PM Reply | Quote 0 Sign in to vote The reason I am using a StringBuilder is so that I can make the string a fixed It will be a function pointer on the C-side after the structure is marshaled. Can you dispel a magic effect you can't perceive? navigate here Join them; it only takes a minute: Sign up Struct marshal in C# up vote 5 down vote favorite 4 I have the following struct in C# unsafe public struct control

You'll be able to ask any tech support questions, or chat with the community and help others. Using the eval command twice Do we know Ford's old name? Based on this, you will need to use Enum.GetUnderlyingType before calling Marshal.SizeOf. How is the correct air speed for fuel combustion obtained at the inlet of the combustor?

Related Sites Visual Studio Visual Studio Integrate VSIP Program Microsoft .NET Microsoft Azure Connect Forums Blog Facebook LinkedIn Stack Overflow Twitter Visual Studio Events YouTube Developer Resources Code samples Documentation Downloads Always use the MarshalAsAttribute.SizeConst field to indicate the size of the array. [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] // OR [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)] public struct SERVER_USB_DEVICE { USB_HWID usbHWID; byte status; bool How can I claim compensation? Sign in using Search within: Articles Quick Answers Messages home articles Chapters and Sections> Search Latest Articles Latest Tips/Tricks Top Articles Beginner Articles Technical Blogs Posting/Update Guidelines Article Help Forum Article

Previous examples of large scale protests after Presidential elections in US? Do we know Ford's old name? Do we know Ford's old name? ByValArray can only be used with arrays.