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Call C# Code From VBA

Create A C# Library

using System;
using System.IO;

namespace SampleComVisibleLibrary {
	public class SampleComVisibleClass {
		public void WriteTimeStampInLogFile() {
			string str = System.Guid.NewGuid().ToString();
			string path = string.Format(@"c:\temp\Log_{0}", str);

			File.WriteAllText(path, DateTime.Now.ToLongDateString());
		}
	}
}

Make C# Class Library Com Visible

1. Right click on the project in solution explorer and click on ‘Properties’.

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2. In the ‘Application’ tab, click on ‘Assembly Information’ button.

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3. A pop-up window will appear. Click on the checkbox ‘Make assembly COM-visible’ and click on ‘Ok’.

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4. Go to the ‘Build’ tab and click on the checkbox ‘Register for COM interop’.

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5. Save the project and compile again.

Register The DLL Using Regasm

1. Open command prompt in administrator mode.
2. In the command prompt, enter the following command

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\RegAsm.exe C:\temp\ComVisibleLibrary\SampleComVisibleLibrary\SampleComVisibleLibrary\bin\Debug\SampleComVisibleLibrary.dll /codebase



In the above command, I am passing the path of the DLL.


3. Press ‘Enter’

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Add Reference Of C# Library In VBA

1. In the code editor, click on Tools - ‘References’

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2. A pop-up window will appear.

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3. Select the C# library i.e. ‘SampleComVisibleLibrary’ and click on ‘Ok’.

Use C# Library

Sub SampleComVisibleAssembly()
	
	Dim obj As New SampleComVisibleClass
	obj.WriteTimeStampInLogFile
End Sub

Output