Call .NET

We 
begin with a simple example: A C#.NET function is called and 
returns the text "Hello CSharp!".

You proceed as follows:

Create a new .NET (VB/C#) project or use an existing project

Important: You must use the .NET Framework, not .NET Core!

Implement the following function, e.g. in a class "testclass.vb""TestClass.cs":

Public Class testclass
    Public Function hellovb() As String

        Dim returnstring As String = "Hello VB!"

        Return returnstring

    End Function
End Class

namespace CSharpGuiXT
{
    public class TestClass
    {
        public string HelloCSharp()
        {
            string returnstring = "Hello CSharp!";
            return returnstring;
        }
    }
}

Compile the project as a class library (DLL):
Use the .NET Framework version 4.0 or higher as the target framework:

Now enter the path to the DLL in the GuiXT profile:

Copy all used DLL files into this directory.

Important: The file guinet.dll, which is included in the GuiXT setup, must also be located in this directory.

Attention: When calling a function, the DLL is loaded into memory and the corresponding file cannot be overwritten. Close all SAP GUI windows before using a modified version.
In a GuiXT Script or InputScript you call the .NET (VB/C#) function using the keyword "CallVB":
GuiXT
```
CallVB msg = utilities.testclass.hellovb

message "&V[msg]"  -statusline
```
```
CallVB msg = Utilities.TestClass.HelloCSharp

message "&V[msg]"  -statusline
```
That means: The .NET (VB/C#) function "hellovb""HelloCSharp" of the class "testclass""TestClass" in the class library "utilities.dll" is called and the result is placed into the GuiXT variable V[msg].

If you are not interested in the return value, you can simply call a .NET (VB/C#) function with

GuiXT
```
CallVB utilities.testclass.hellovb
```
```
CallVB Utilities.TestClass.HelloCSharp
```
to call it.

As a result, an SAP GUI message appears with the text from the .NET (VB/C#) function: