Windows DLL for Morovia Barcode Fonts

Introduction

To assist our customers integrating barcode fonts with their own applications, we provide a series of source code written in a variety of languages, such as Visual Basic, VBA, VBScript, C/C++, Delphi, FoxPro and JavaScript. You are allowed to import and modify these source code to fit your applications.

However, some customers asked to be provide a Windows DLL for their programming environment. This benefits some old applications which accept only DLL interfaces.

This Windows DLL applies to the following font products: Code39, Code39 Full ASCII, Code93,Code128, code25, Code11, Codabar, I2of5, UPC/EAN/Bookland, US Postal, RoyalMail and Telepen. Other font products, such as OCR, MICR E-13B and CMC7, require no check digit calculation at all.

This Windows DLL does not apply to 2D symbology font products such as PDF417 Fontware and DataMatrix Fontware. Contact support@morovia.com to get the DLL version of the encoders.

The Windows DLL is included in the Morovia Font Tools which can be downloaded from here.

Function Prototypes

The function prototypes are the same as the ones in other languages. Click here for the list of the function prototypes.

How to use DLL functions in Visual Basic

We recommend you place our DLL under the Windows directory, or you can place the DLL under the same folder of your application. In either case you need to make sure that the DLL is searchable in your application.

Declaring a DLL procedure

The first step is to declare the procedure in the Declarations section of a module:

Private Declare Function Code128Ex Lib "MrvFontTools" _ Alias "Code128Ex" _
				( ByRef lpString As String) As String 

To get the definition of the function, refer to the function prototype. If you place the Declare in a Form or Class module, you must precede it with the Private keyword. You only need to declare the function once per project; you can then call it any number of times.

Calling a DLL procedure

After the function is declared, you call it just as you would a standard Visual Basic function. Here, the procedure has been attached to the Form Load event:

Private Sub Form_Load()
      TextBox1.Text = Code128Ex("00001344556")
End Sub

When this code is run, the function first calculates the barcode string for the specified data in Code128 format. If the text box is formatted with appropriate Code128 font, a code128 barcode will appears on the form.

How to Use DLL functions in C/C++

There are two ways to use DLL functions in C/C++. The first method is to use an import library file. If you are working on this approach, write to support@morovia.com to obtain a C/C++ header file and the import library. Compile your application and link with the import lib. Another robust way is to dynamically load the DLL into the memory, obtain the function address and call the function. The following code demonstrates how to:

 #include <windows.h>
 #include <iostream.h>
 #include <stdio.h>
 #include <conio.h>

 #define MAXMODULE 50

 typedef char* (WINAPI*cfunc)(const char*);

 cfunc encode_func;

 void main() {
   
       HINSTANCE hLib=LoadLibrary("MrvFontTools.DLL");
       if(hLib==NULL) {
            cout << "Unable to load library!" << endl;
            getch();
            return;
       }
       encode_func=(cfunc)GetProcAddress((HMODULE)hLib, "Code128Ex");

       char* p = encode_func("0001233000");
       FreeLibrary((HMODULE)hLib);
       getch();
 }