CALLdotNET

The CALLdotNET command allows BASIC to call any .NET assembly and is useful when using third party applications.

COMMAND SYNTAX

    CALLdotNET NameSpaceAndClassName, methodName, param SETTING ret \
               [ON ERROR errStatment]

In order to use CALLdotNET, you need:

• The .NET Framework
• The dotNETWrapper.dll installed somewhere to where your PATH points.

NOTE

The dotNETWrapper is loaded dynamically at runtime; therefore, a compiled basic application has no dependencies on the .NET Framework. Loading the framework takes between 5 and 7 seconds. However, this only occurs when calling the .NET method for the first time.

SYNTAX ELEMENTS

NameSpaceAndClassName The "full" NameSpace (e.g., myNameSpace.myClass)

methodName The name of the .NET in this class (e.g., "myMethod")

Param Any parameter (eg DynArray)

EXAMPLE

In C#:

     using System;
     using System.Windows.Forms;
     namespace myNameSpace
     {
 	    public class Class1
 	    {
 		    public string sayHello(string str)
 		    {
 			    return "Thank you, I received : " + str;
 		    }
 		    public Class1(){}
 	    }
     }

In VB.NET:

     Namespace myNameSpace
       Public Class Class1
           Public Function sayHello(ByVal str As String) As String
             Dim sAnswer As String
             sAnswer = InputBox(str)
             sayHello = sAnswer
           End Function
       End Class
     End Namespace

Note: Create the .NET project as a 'Class Library'.

If using the visual studio IDE, this option is on selected when creating a new project:

If using .NET SDK (instead of the IDE) to compile class libraries into a 'DLL' file, the 'csc' (C# Compiler) or 'vbc' (Visual Basic .NET compiler) command can be used from the command line:

     csc /out:myNameSpace.dll /target:library sourcefile.cs

The name of the '.DLL' created must be the same as the 'namespace' as used in the class library t locate the 'dotNetWrapper.dll' library:

After creating the library, place it in the same private directory as the application. (i.e. the same directory as the jBC executable that will call the class) This is a requirement of the .NET paradigm and not TAFC. The directory should also be in the PATH environment variable.

To call these methods from Basic:

    CALLdotNET 'myNameSpace.Class1', 'mymethod', p SETTING ret
    CRT ret

ON ERROR

You can manage any errors, which occur during the call, at the BASIC level by getting the SYSTEM(0) variable.

This variable can have the following values:

EXAMPLE

BASIC code using the ON ERROR would look like this:

    PROGRAM testCALLdotNET
        ns.className = ''
        methodName = ''
        param = ''
        CRT "Please enter NameSpace.ClassName : "
        INPUT ns.className
        CRT "Please enter a Method Name : "
        INPUT methodName
        CRT "Please enter a Parameter : "
        INPUT param
        CALLdotNET ns.className, methodName, param SETTING ret \
            ON ERROR GOSUB errHandler
        CRT "Received back from .NET : " : ret
        STOP
    *
    errHandler:
        err = SYSTEM(0)
        BEGIN CASE
        CASE err = 2
           CRT "Cannot find dotNETWrapper.dll"
        CASE err = 3
           CRT "Class " : className : "doesn't exist !"
        CASE err = 5
           CRT "Method " : methodName : "doesn't exist !"
        END CASE
        RETURN