sqlite3 not found but it was already added as reference - c#

System.DllNotFoundException was unhandled Message=Unable to load DLL 'sqlite3': The specified module could not be found.
I already reference the DLL. I check it on Debug folder and it was there. I also search how to "include" it in the project but they don't specifically explain how to do it.
I'm following this example: http://www.codeproject.com/Articles/22165/Using-SQLite-in-your-C-Application

SQLite doesn't have a full .NET implementation, but available libraries are wrappers of a native one.
This means that not only .NET assembly must be referenced but you need to be sure native library is there too when applicacion is executed.
Summary: output folder will have a .NET assembly and a native assembly (C/C++ one) in order to work properly!

The System.Data.SQLite.dll is platform dependent assembly, and you mast add reference to appropriated assembly.

Follow the steps :
1)Add the Dll in debug folder
2)in your code add this
using System.Data.SQLite;
3) Add the reference by going to solution explorer and add it.
4) Check the version in app.config to verify it

Related

C# .NET - Adding DLL as reference won't work

I am trying to add a DLL as a reference to my project (64bit on VS2010 with the .NET Framework 4). But I am getting the following error:
A reference to 'XXX' could not be added. Please make sure that the file is accessible, and that it is a valid assemlby or COM component
Installing the DLL with RegSvr32 says:
The module was loaded but the entry-point DLLRegisterServer was not found...
Trying installing the DLL with RegAsm says:
error RA0000: "XXX" could'nt be loaded, because it's no valid .NET Assembly.
I have no idea hwat kind of DLL that is, but that it is contained inside a SDK which was written for the .NET Framework and in C#.
Can anyone help me with this?
Thanks a lot!
Sorry for my english:
either the dll is dll building for c# (managed) and you have just to add reference to your project : (right click on reference and select "add reference") -> you have to indicate where is locating your dll. After when you need to access at your Dll, you have to include the namespace.
either is not a dll building for c# you have to load the dll by using loadlibray
either your dll is corrupted..

Referencing a .dll that has already been merged with Fody/Costura

I have an app that references a .dll that was built with Costura/Fody i.e The dll has all its references embedded. When I run the console app, the references from the dll are not unpacked so the console app throws an exception saying missing .dll etc. as it needs those resources to run.
i.e. AssemblyA.dll embeds MyAssembly.dll when built with Costura/Fody. ConsoleAppC references and embeds AssemblyA.dll but also needs MyAssembly.dll to run. I do have a reference to MyAssembly.dll in ConsoleAppC so that it will compile (but CopyLocal is set to false). I was thinking that MyAssembly.dll would be made available to ConsoleAppC when AssemblyA.dll's embedded resources are unpacked?
This is not working but is my scenario valid in any way or can you only utilise embedded resources from ConsoleAppC and not the ones that were embedded in AssemblyA.dll?
Thanks in advance for any help
Mike
What you're trying to do isn't possible with Costura.Fody. What Costura does is embed libraries directly into the main assembly. This means that if you embed the built assembly into another project, it can't see the sub assemblies.
For example, consider the following project structure:
AssemblyA
Foo.cs
References:
SubAssembly1.dll
SubAssembly2.dll
SubAssembly3.dll
AssemblyB
Assume that Costura.Fody is used to embed the sub assemblies in AssemblyA, creating a single DLL file, AssemblyA.dll
If you embed AssemblyA.dll in AssemblyB, then you will not be able to access classes in SubAssembly1.dll. You will only be able to see any of the classes that are directly in AssemblyA.dll, such as those contained in Foo.cs - you will not be able to see any of the libraries referenced by/embedded in AssemblyA.dll.
See this answer to a similar question, where the answerer suggests using ILMerge instead.

Could not load type 'myinterface' from assembly

I have a solution that includes several projects. A few are libs that are building dll's used in my main project in this solution.
My main project builds with output type console application.
This all works fine.
When i change the build output type to a class library (since i want to use this project as a plugin eventually). The project will still build, this time to a dll.
When i use this plugin in an application where i use it as a dll however, it will run up to a certain point where it's trying to load a type defined in an external dll (so NOT built by my solution) and throw the exception:
Could not load type 'externalinterface' from assembly 'externallib, version=3.0.0.0, Culture=neutral, PublicKeyToken=null'.
The dll's are all in the correct folder,etc.
Also worth noting, the plugin is tested in another location than where i built it. The executable still works on this location, the dll/plugin does not. Same amount of dll's in their folders etc.
EDIT: I already used ILSpy (dll inspector) to open the actual dll that is being referenced (so externallib in the errormessage) and checked if 'externalinterface' was present and it is.
EDIT2: RESOLVED! The program that loaded my plugin was loading the same dll that caused the exception. The dll it loaded was of another version than the one i loaded.
Check whether the type externalinterface is present in the referred dll.
You didn't include the details of the exception the application is throwing. However, based on the message you gave, it appears your assembly does not have a strong name. If the application attempting to load your assembly as a plugin does have a strong name, then .NET will require all assemblies loaded by it also have a strong name, so you need to configure your assembly to have a strong name before continuing.
Maybe some supported dll's which is used by the 'externalinterface' is missing in the target machine. In the target machine, check is all the necessary dll's are present in the output folder.
Or blindly copy paste all the dlls in the output folder from the machine where the code is working to the target machine where you have the problem. After this, if the code is working in the target machine, then try to analyze which supporting dll you are missed to copy.

How to bundle a required DLL with a solution in Visual C# (Express, 2010)

I have an application written in C# which interfaces with some custom hardware using a vendor supplied .Net assembly. The .Net assembly in turn loads another DLL at run time. I can add the vendor supplied assembly to my project but when I run it, the vendor assembly complains that it can't load the required DLL. I can work around this for the moment by copying the DLL to the bin\Debug and bin\Release folder.
The problem is that I will need to distribute this application to clients at some point and they will not have this DLL in place. I can't see how I can make the solution require it; I can't add it as a reference since I get the error "A reference to foo.dll could not be added. Please make sure that the file is accessible, and that it is a valid assembly or COM component."
I can't convert the DLL to a .Net assembly using TlbExp, it gives an error "The module was expected to contain an assembly manifest."
I thought if I published the application via "click once" that I could declare the dependency there but I don't see any way for this either. I also tried adding it as a file resource but this didn't seem to help.
I can see other questions on SO relating to how to invoke functionality in an external DLL but in this case, I just need a way to bundle the DLL with the project.
Thanks.
Indicates that the attributed method is exposed by an unmanaged dynamic-link library (DLL)
The DllImportAttribute attribute provides the information needed to call a function exported from an unmanaged DLL. As a minimum requirement, you must supply the name of the DLL containing the entry point.
For further reference go here
Link to Review
You could add the dll as a resource, write it out as a byte[] to a file on loading, and do an Assembly.Load() at runtime for deployment.
You might have to use an AppDomain.AssemblyResolve Event to make sure the assembly resolves in case of multiple versions.
you could add both (all) of the dlls in your project as references and mark them as "copy local". That should do it unless the first DLL expects the second DLL in a specific place.

Using managed C++ dll from C#

I've created a dll using managed C++. Now I'm trying to use it from C#. I've added the Object to project references. Object browser shows the object in the dll correcly, path to the dll in object browser corresponds to the actual path.
However, when I run the C# program it complains:
Unhandled Exception: System.IO.FileNotFoundException: The specified module could
not be found. (Exception from HRESULT: 0x8007007E)
Any idea what else have to be done?
Thanks.
I think that you're missing the other assemblies or dll's references by your managed C++ assembly.
Does your managed C++ assembly have an other dependencies, including unmanaged dlls? You'll see this error at runtime if your referenced assembly fails to load a dependency.
Are you running the application in release on a machine without VS installed?
I only ask because I ran into a similar problem here: Mixed Mode Library and CRT Dependencies - HELP
if you scroll down to my answer you can see what I did that helped me.
Check that the c++ assembly is present in the same folder as your c# program. It should be copied over automatically if the 'Copy Local' property is set to true (on the reference to the c++ dll in your c# app).
If the c++ dll is there, the most likely problem is that the c++ dll depends on another non-managed dll which cannot be found (i.e. c# will not copy these to your app folder because it does not know about unmanaged references). You can use DependencyWalker on the c++ dll to check for missing dependencies.
Another probable couse could be a problem with your MSVC runtime dlls. see if DependencyWalker complains about missing MSVCR*.dll, MSVCP*.dll etc... files.

Categories