Advancing common function calls from VB6 to VB.NET

Summary This topic shows ArcGIS developers how to take advantage of the .NET Framework best practices for common function calls when advancing their custom applications from Visual Basic 6 (VB6) to Visual Basic .NET (VB .NET).

About advancing common function calls from VB6 to VB .NET

In VB6, performing common functions with the Windows Operating System (OS) was done by Win32 application programming interface (API) calls. VB .NET continues to honor this VB6 programming practice for legacy purposes but this is highly undesirable because inappropriate Win32 API calls can crash the Windows OS. The preferred VB .NET alternative is to take advantage of the vast .NET Framework set of libraries to perform the same types of common functions. For the .NET Framework equivalents to the Win32 API calls, see Microsoft Win32 to Microsoft .NET Framework API Map on the Microsoft Developer Network (MSDN) Web site.
The following table shows some of the more common input/output (I/O) Win32 functions and their equivalent in the .NET Framework System.IO assembly:
Win32 function
.NET Framework API
CopyFile
System.IO.File.Copy
CreateDirectory
System.IO.File.Directory.CreateDirectory
GetCurrentDirectory
System.IO.File.Directory.GetCurrentDirectory
ReadFile
System.IO.File.FileStream.Read
SearchPath
System.IO.File.Exists
The following table shows some of the more common printer related Win32 functions and their equivalent in the .NET Framework System.Drawing.Printing assembly:
Win32 function
.NET Framework API
EnumForms
System.Drawing.Printing.PrinterSettings.PaperSizes
EnumPrinters
System.Drawing.Printing.PrinterSettings.InstalledPrinters
GetDefaultPrinter
System.Drawing.Printing.PrinterSettings constructor
System.Drawing.Printing.PrinterSettings.PrinterName
GetForm
System.Drawing.Printing.PrinterSettings.PrinterName
GetPrinter
System.Drawing.Printing.PrinterSettings.PrinterName
System.Drawing.Printing.PrinterSettings properties
SetPrinter
System.Drawing.Printing.PrinterSettings.PrinterName
System.Drawing.Printing.PrinterSettings properties
DeviceCapabilities
System.Drawing.Printing.PrinterSettings properties
The following table shows some of the more common Graphic Device Interface (GDI+) drawing Win32 functions and their equivalent in the .NET Framework System.Drawing assembly:
Win32 function
.NET Framework API
BitBlt
System.Drawing.Graphics.DrawImage
CreateBitmap
System.Drawing.Bitmap constructor
CreatePen
System.Drawing.Pen constructor
GetDC
System.Drawing.Graphics.GetHdc
ReleaseDC
System.Drawing.Graphics.ReleaseHdc
GetDeviceCaps
System.Drawing.Graphics properties
System.Drawing.Printing.PrinterSettings
Rectangle
System.Drawing.Graphics.DrawRectangle
Calls to System.Drawing should not be used to render graphics within any ArcObjects components or controls (such as, the ArcMap map window or the ArcGIS Engine map control). Using System.Drawing operations on ArcObjects components and controls is not supported by ESRI. Use System.Drawing operations on Microsoft controls and components (such as, Microsoft Windows forms or Microsoft image control). 


See Also:

Migrating from VB6 to VB.NET
General steps for migrating from VB6 to VB.NET



Development licensing Deployment licensing
ArcView ArcView
ArcEditor ArcEditor
ArcInfo ArcInfo
Engine Developer Kit Engine Runtime