how can i access C# dll from VBScript on client machine - c#

i have created a C# dll file on my machine as shown below:
namespace myDLL
{
public class myClass
{
public string myFunction()
{
return "I am Here";
}
}
}
then i created a tlb file with "tlbexp" command,
then i used the "regasm" command n registered this dll on my machine.
When i created an object of type myClass on my machine using VBScript, everything is working fine... here i used the CreateObject() method as shown below:
Set myObj = CreateObject("myDll.myClass")
Now i want to create an object of type myClass from VBScript that is running on another machine, how can i do this. please help me how can i access that dll file, am using the CreateObject() function as shown below:
Set HD = CreateObject("myDll.myClass","myMachineName")
now am getting error as "permission denied".

It appears that this is supported if the assembly is built with as COM visibility enabled.
Is it possible to execute a .NET assembly(dll) from vbscript?
By the way, I was pretty delighted to find out that there is a JScript compiler for .NET which allows one to write .NET code using JScript and also to target other .NET assemblies but unfortunately I haven't found anything similar for VBScript.

Related

Why does my C# COM visible DLL always return #VALUE! in Excel VBA?

I am writing a C# DLL which must be COM visible as it's main use case will be embedded into Microsoft Excel VBA (I know). Whilst developing I have been using Visual Studio's "Register for COM Interop" checkbox and having the process done for me. This has been working fine on my PC as I am able to get valid outputs in Excel, however now I am trying to register the DLL on client machines (manually) and I seem to be having issues with making valid calls as Excel only returns !VALUE.
This following has been my process:
AssemblyInfo.cs:
[assembly: ComVisible(true)]
Class1.cs:
namespace ManualRegister
{
public class Class1
{
public string test()
{
return "Working!";
}
}
}
Copy ManualRegister.dll into SysWOW64
Register.bat:
cd/
C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe ManualRegister.dll /tlb:ManualRegister.tlb /codebase
pause
Adding reference to VBA module.
VBA Code:
Function test()
Dim object As New ManualRegister.Class1
test = object.test()
End Function
VBA error:
Can anyone see what step I'm missing / doing wrong?
(I have also tried specific CPU architecture builds to no avail)

How to solve .NET C# GDAL PINVOKE error in class library?

I'm building an extension for a program (.NET Class library) where I want to use GDAL. I have installed GDAL and GDAL.Native via Nuget. I previously tested my function in a separate Console App, and everything was working fine.
But when I use the function in my Class Library and load it into the program, it's giving an error during the GdalConfiguration:
The type initializer for 'OSGeo.GDAL.GdalPINVOKE' threw an exception. at OSGeo.GDAL.GdalPINVOKE.SetConfigOption(String jarg1, String jarg2)
at OSGeo.GDAL.Gdal.SetConfigOption(String pszKey, String pszValue)
at MyGdal.GdalConfiguration..cctor() in C:....MyGdal\GdalConfiguration.cs:line 98
In Line 98 the configuration for variable "GDAL_DATA" is set:
// Set the additional GDAL environment variables.
string gdalData = Path.Combine(gdalPath, "data");
Environment.SetEnvironmentVariable("GDAL_DATA", gdalData);
Gdal.SetConfigOption("GDAL_DATA", gdalData);
Does anyone know why this variable cannot be set when using the function in the program but it works when using it in a Console App? I have tried to reference the Console App to my Class Library and call the function from there, but it is giving te same error.

Create new Excel Function (User Defined Function) using C#

I would like to create a new Excel function (user Defined Function), for that i did the same steps as in this link: https://excel-dna.net/
I created a class Library Project
I installed the package ExcelDna.Integration
I created a method sayHello
But when i try to call my function from a cell in excel (i put =sayHello("World"), the function didn't appear, it seems it's not added to excel functions.
is there some missing steps? how can i make my function appear to be able to use it ?
You should install the package "ExcelDna.AddIn" to make the add-in (that will set up the add-in including the important .dna file, and also bring in the "ExcelDna.Integration" reference library).
So the steps would be:
Create a new C# Class Library project (targeting .NET Framework not .NET Standard)
Install the ExcelDna.AddIn package
Add some code, e.g.
public static class MyFunctions
{
public static string SayHello(string name) { return "Hello " + name; }
}
Press F5 to compile and load the add-in in Excel
(Note that on some Excel installations, the Debug setting for the project get an extra %1 in the executable path - just remove this from the end if you get an error when debugging)
The best support for Excel-DNA is the Google group at https://groups.google.com/forum/#!forum/exceldna

Calling C# code within Python3.6

with absolutely no knowledge of coding in C#, I wish to call a C# function within my python code. I know there's quite a lot of Q&As around the same problem, but for some strange reason, i'm unable to import a simple c# class library from a sample python module.
Here's below as to what i've done -
C# Class Library setup
I'm using the VS 2017 CE.
I create a new project TestClassLibrary under the type of ClassLibrary(.NET Standard)
The classes inside the project are as follows -
MyClass.cs
using System;
namespace TestClassLibrary
{
public class MyClass
{
public string function()
{
return "Hello World!";
}
}
}
This was built successfully, generating the .dll file under the \bin\Debug\netstandard2.0 dir as TestClassLibrary.dll
Now, I switch over to python3.6 (running on a virtualenv, backed with pythonnet 2.3.0)
main.py
import sys
sys.path.append(r"<Ablsloute Path to \bin>\Debug\netstandard2.0")
import clr
clr.AddReference(r"TestClassLibrary")
from TestClassLibrary import MyClass
When i Run python main.py, the code fails with the error -
Traceback (most recent call last):
File "main.py", line 6, in <module>
from TestClassLibrary import MyClass
ModuleNotFoundError: No module named 'TestClassLibrary'
Should the code be -
import sys
sys.path.append(r"C:\Users\DELL\source\repos\TestClassLibrary\TestClassLibrary\bin\Debug\netstandard2.0")
import clr
clr.AddReference("TestClassLibrary.dll")
from TestClassLibrary import MyClass
I get -
clr.AddReference("TestClassLibrary.dll")
System.IO.FileNotFoundException: Unable to find assembly 'TestClassLibrary.dll'.
at Python.Runtime.CLRModule.AddReference(String name)
But when i ran the code below, the code runs as expected -
import clr
clr.AddReference(r"System.Windows.Forms")
from System.Windows.Forms import MessageBox
MessageBox.Show("Hello World!")
I've no idea of what i might be missing :(
This is really janky but how I like to do things that are personal projects.
Python lets you send stuff to the command line really easily. C# can be run from command line. You probably see where I'm going with this.
Try adding C sharp to PATH. import os to python. then use this line of code when you want to run the C# script:
os.system("csc nameofscript.cs")
perhaps I've misunderstood, but this is how I would make it work on my machine

A Simple C# DLL - how do I call it from Excel, Access, VBA, VB6?

I have a simple class library written in c#.
using System;
namespace TestDll
{
public class Test
{
public string HelloWorld
{
get
{
return "Hello World";
}
}
}
}
My question is how can I call this HelloWorld function from Microsoft Office Visual Basic (which I think is VB6)?
My first step was to add the DLL as a reference - but on browsing and selecting the compiled DLL the message "Can't add a reference to the specified file." was thrown.
Can anyone point me in the right direction as to why/how to get this working?
Thanks in advance SO!
You can't access a static member via COM interop. In fact your code doesn't even compile, the method should be in a class. Here is how you can do it:
[InterfaceType(ComInterfaceType.InterfaceIsDual)]
[Guid("01A31113-9353-44cc-A1F4-C6F1210E4B30")] //Allocate your own GUID
public interface _Test
{
string HelloWorld { get; }
}
[ClassInterface(ClassInterfaceType.None)]
[Guid("E2F07CD4-CE73-4102-B35D-119362624C47")] //Allocate your own GUID
[ProgId("TestDll.Test")]
public class Test : _Test
{
public string HelloWorld { get { return "Hello, World! "; } }
}
The project properties Build tab, select Register for COM interop. So you can see the results quickly. To install the dll on another machine you need to use regasm.
To then consume this:
Dim o : Set o = CreateObject("TestDll.Test")
MsgBox o.HelloWorld
You can also reference the dll and use early binding:
Dim o As TestDll.Test
Set o = New TestDll.Text
MsgBox o.HelloWorld
And to expand on registering the DLL on different computers.
Once you compile and build the above code on your development machine, if you have
The project properties Build tab, select Register for COM interop.
your Visual Studio output folder (usually bin\Debug) where the compiled *.dll is found will also have a *.tlb file.
This *.tlb file is a 'Type Library'. And is needed by the client machine to understand the different 'Types' in your *.dll and to basically tell the client machine how to use it.
By setting the above 'Register for COM interop' -- aswell as a *.tlb file being produced, the assembly(dll) is registered on your machine, and is therefore accessible.
In VBA you can now add this file as a reference by
VBA Editor -> Tools -> References -> Browse -> Select
this will allow you to then declare the classes found in your library.
Dim TestClass As Test
Set TestClass = New Test
MsgBox TestClass.HelloWorld
HOWEVER - if you want to then use your dll on a different client machine, you will have to use regasm.exe - to register the assembly(dll) on that machine.
This can be done by the command line,
regasm.exe
in this case
regasm.exe TestDll.dll
once you have registered the assembly on the new client machine, you will be able to access it by again adding a reference to its *.tlb
Hope this helps!
Just wanted to comment that in Visual Studio 2008, to get the .tlb file generated you must also go under the Application | Assembly Information and select "Make Assembly COM visible". Took me a while to find that, so hope it helps others out.
To add to AnthonyWJones's good answer, you'll also need to register your DLL using Regasm.exe which adds the necessary registry entries.

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