Friday, October 05, 2007

DN4DP#23: .NET only: Obsolete features

This post continues the series of The Delphi Language Chapter teasers from Jon Shemitz’ .NET 2.0 for Delphi Programmers book.

The previous post showed how to use the mysterious P/Invoke features. This time we'll list the Win32 specific features of the language and RTL that didn't make it to the .NET side.

Note that I do not get any royalties from the book and I highly recommend that you get your own copy – for instance at Amazon.

"Obsolete features

Due to the managed and garbage collected nature of the .NET environment, a number of native Win32 specific features had to be left out in the Delphi for .NET language. Most of these are already warned against when you compile with the Win32 compiler, easing the porting process.

Feature    Comment
Pointers  Including PChar, @ operator, GetMem, etc. See Unsafe code
absolute    Variable overlaying not supported
Real48   This is a relic from the Borland Pascal (BP) days
File of <type> Size of records are not fixed in .NET
BlockRead, BlockWrite Size of records are not fixed in .NET
Old-style objects  Really a relic from BP – deprecated since Delphi 1
BASM   Built-in Assembler – is specific to x86 and native code
IUknown   No longer has AddRef, Release and QueryInterface
implements   Interface delegation, not implemented yet
automated, dispid  OLE Automation not supported


1 comment:

Unknown said...

Old-style objects Really a relic from BP – deprecated since Delphi 1

Which is a pity, because it's much cleaner that that piece of junk they introduced as 'Tobject'. Conceptually sound, implementationwise nothing but codebloat.

Copyright © 2004-2007 by Hallvard Vassbotn