Validation tutorial

This tutorial demonstrates how to create a plug-in that validate fields using Microsoft Visual Basic 6.0. In this tutorial you will:

Create a DLL that subscribes to a ReadSoft Invoices event.
Connect the plug-in to ReadSoft Invoices via Eilocal.ini.

Create an ActiveX DLL project

Create a new ActiveX DLL project using Microsoft Visual Basic 6.0.
Rename the project to "myValidation" and rename the default class module to "clsServer". You will use these names later when you add the plug-in to Eilocal.ini.
Add a reference to the ReadSoft Invoices type library.

The class code

The myValidation plug-in has these functions:

Connect: Connects to a ReadSoft Invoices module and subscribes to the AppStarted event in the Manager module.
OnInvoiceComplete: Contains code for validating invoice fields.
ConfigurePlugin: Determines what happens when the Configure button is clicked in the Extension programs dialog in the Manager module.
Disconnect: Releases memory allocated by the plug-in.

Copy and paste the code below into the clsServer module.s

Option Explicit

' Declare a reference to the Application object

Private objEHApplication As EHICOM.Application

 

Public Function Connect(objEHIApp As Object, sIniFile As String, sIniSection As String) As Long

    Set objEHApplication = objEHIApp   ' Save the application object for future references

    ' Setup the subscriptions

    Select Case objEHApplication.ModuleType

        Case eiManager

        Case eiScan

        Case eiInterpret

            objEHApplication.Subscribe Me, "InvoiceComplete", "OnInvoiceComplete"

        Case eiVerify

            objEHApplication.Subscribe Me, "InvoiceComplete", "OnInvoiceComplete"

        Case eiTransfer

        Case eiOptimizer

   End Select

   Connect = evtOK

End Function

 

Public Function ConfigurePlugin() As Long

' Called by clicking the Configure button

    MsgBox "No configuration is available for this plug-in"

    ConfigurePlugin = evtOK

End Function

 

Public Function OnInvoiceComplete() As Long

   

    On Error GoTo OnInvoiceCompleteException

   

    ' Get a reference to the current invoice,

    ' since we will be using that object frequently.

    Dim objInvoice As Invoice

    Set objInvoice = objEHApplication.CurrentInvoice

   

    ' Get references to all the fields you need.

    ' Note that the following lines might throw an exception

    ' (caught by the error handler) if the fields do not exist.

    Dim objNetField As InvoiceField, objVatField As InvoiceField, objTotalField As InvoiceField

    Set objNetField = objInvoice.Fields("Net_Amount")

    Set objVatField = objInvoice.Fields("VAT_Amount")

    Set objTotalField = objInvoice.Fields("Total_Amount")

    ' Validate net + vat against total

    ' We use the "Val" VB function to convert the string value to a numeric before

    ' performing any arithmetic operations.

    ' This function requires decimal char to be a point (.)

   

    ' A better way would be to use the DisplayString property of the field,

    ' and then use the information found in Eiglobal.ini (DisplaySettings)

    ' to convert the string correctly.

    If (Val(objNetField.Value) + Val(objVatField.Value)) <> Val(objTotalField.Value) Then

        ' Total does not match net + vat. Warn the user if in Verify.

        If objEHApplication.ModuleType = eiVerify Then

            MsgBox "Balance not zero, captured total does not match calculated total"

        End If

        ' Set validation error on one of the fields (we do not know which one is incorrect).

        objTotalField.Status = eiFieldValidationError

    End If

   

   ' Return evtOK

   OnInvoiceComplete = evtOK

   Exit Function

 

' Error handler

OnInvoiceCompleteException:

    ' Only display a message if in Verify.

    If objEHApplication.ModuleType = eiVerify Then

        MsgBox "Internal error:" & vbNewLine & Err.Description

    End If

    OnInvoiceComplete = evtError

End Function

 

Public Function Disconnect(objEHIApp As Object) As Long

    ' Release memory

    Set objEHApplication = Nothing

    ' Return evtOK

    Disconnect = evtOK

End Function

Save the project.
Build the DLL and copy it to ReadSoft Invoices's Bin folder.

Add the plug-in to Eilocal.ini

In order to use the plug-in, it must be specified in Eilocal.ini. The sample below shows a typical Manager plug-in section with the HelloWorld plug-in highlighted.

Manager

[Plugins::eimngr]

Plugin1=Common

Plugin2=Manager

Plugin3=DBAdmin

Plugin4=myValidation

[eimngr::Common]

Name=Common Dialogs

Type=COM

SupportIDispatch=TRUE

Classname=ReadSoft.INVOICES.GUI.Extensions.Plugin

[eimngr::Manager]

Name=Manager Dialogs

Type=COM

SupportIDispatch=TRUE

Classname=eimngrdlg.cserver

[eimngr::myValidation]

Name=myValidation

Type=COM

SupportIDispatch=TRUE

Classname=myValidation.clsServer

After you save Eilocal.ini, you can run an Interpret or Verify job to see the results.

Microsoft Visual Basic automatically registers DLLs when you make them from the File menu. If you want to use a plug-in on another computer, you must register the DLL on that computer.