The Delphi Preview Handler, is a preview handler for Windows Vista, 7, 8 and 10 which allows you to read your source code with syntax highlighting without having to open it in an editor.

This preview handler can render the following file extensions:

Extensions	Description	Preview
.pp , .pas, .lpr, .lpk, .lfm, .inc	Free Pascal/Lazarus Files
.pas, .dpr, .dpk, .inc, .dproj, .bdsproj	Delphi Files
.c, .cpp,. cc,.h, .hpp,.hh, .cxx, .hxx, . cu	C and C++ source Files
.asm	Assembler source files
.e, .ace	Eiffel files	.
.f, .for	Fortran files	.
.java	Java files	.
.csproj, .xaml, .sln, .vcxproj, .vbproj, .jsproj, .appxmanifest	Visual Studio files
.bas, .vb	Visual Basic files	.
.cbl, .cob	COBOL files	.
.cs	C# files
.css	Cascading Stylesheet files
.htm, .html	HTML Documents
.js	Javascript files
.php, .php3, .phtml	PHP files
.vbs	VBScript files	.
.bat, .cmd	MS-DOS Batch Files	.
.dfm, .xfm	Borland Form Files	.
.pl, .pm, .cgi	Perl Files
.py	Python files
.rb, .rbw	Ruby files
.sh	UNIX Shell Scripts	.
.sql	SQL files
.iss	Inno Setup Scripts
.ini	INI files	.

• Supports Windows Vista, 7, 8 and 10 on 32 and 64 bits.
• +50 syntax highlight themes.
• +60 source code extensions supported.
• Themes compatibles with the Delphi IDE Theme Editor

In order to avoid problems you must follow these steps when you install or register a new version of the preview handler.

1. Close all the windows explorer instances which have the preview handler active or the preview handler was used (remember the dll remains in memory until the windows explorer was closed).
2. Unregister the previous version executing the uninstaller located in C:\Program Files (x86)\TheRoadToDelphi\DelphiPreviewHandler or C:\Program Files\TheRoadToDelphi\DelphiPreviewHandler
3. If you install the preview handler manually you must unregister using the UnRegister.bat running as admin.
4. Now proceed with the installation of the new version.