## Sunday, January 10, 2010

### Building a COM Interop Assembly to use with Microsoft Dexterity

I am currently building some customizations for a customer of mine in the aerospace industry. My customer required a library of trigonometric functions that could be used to extend their Dexterity integrating applications.

To solve this problem, we turned to .NET to create COM interop assembly. The idea was to take advantage of the standard Math class methods available with the System namespace - System.Math . The following is an excerpt of the code we created:

TrigonometricFunctions.cs
`//Created by Mariano Gomez, MVPusing System;using System.Collections.Generic;using System.Text;using System.Runtime.InteropServices;namespace TrigonometricFunctions{    public class TrigonometricFunctions    {        [GuidAttribute("8268A95E-6FCB-4FB2-88A1-1E38F49F4FB8"), ClassInterface(ClassInterfaceType.AutoDual)]        public class TrigFn        {            // dx in degrees            public double fSin(double dx)            {                double angle = Math.PI * dx / 180.0;                // returns sin(dx)                return Math.Sin(angle);            }            // dx in degrees            public double fCos(double dx)            {                double angle = Math.PI * dx / 180.0;                // returns cos(dx)                return Math.Cos(angle);            }            // dx in degrees            public double fTan(double dx)            {                double angle = Math.PI * dx / 180.0;                // returns tan(dx)                return Math.Tan(angle);            }        }    }}`

Once the functions in the TrigFn class were in place, we set up the assembly information in Visual Studio's marking the option to Make assembly COM visible. So we did not have to register the assembly manually, we took advantage of Visual Studio's ability to register the assembly for COM interop under the Build settings. For purposes of demostration, I created a simple Dexterity form, as shown below: The following is the code added to the '(L) Sine' button:

Sine button CHG script
`{ script: l_Sine_CHG }local TrigonometricFunctions oTrig;local currency angle, sine;oTrig = new TrigonometricFunctions.TrigFn();'(L) Prompt' = "The Sine value is ";'(L) Conversion' = oTrig.fSin('(L) Angle');`

In the code above, TrigonometricFunctions is a data type created after adding the TrigonometricFunctions COM interop assembly as a library to our Dexterity application. The data type references the TrigonometricFunctions.TrigFn class.

References:

• Using a .NET Assembly from a Dexterity-Based Application - Click here
• Microsoft Dynamics GP 10.0 White Paper: Using a .NET Assembly from a Dexterity-based Application - Click here

Until next post!

MG.-
Mariano Gomez, MVP 