常见语言：
c行注释：none块注释：扩展名：.c/.h
c++行注释：//这里是注释块注释：扩展名：.cpp/.h
c#行注释：//这里是注释块注释：xml注释：///这里是xml注释扩展名：.cs
vb
行注释：'这里是注释
块注释：none
扩展名：.bas
java行注释：//这里是注释块注释：扩展名：.java
vb.net行注释：'这里是注释块注释：nonexml注释：///这里是xml注释扩展名：.vb
perl行注释：#这里是注释块注释：none扩展名：.pm
html行注释：none块注释：扩展名：.htm/.html SQL行注释：--块注释：
Comment comparison
There is a wide variety of syntax styles for declaring comments in source code. BlockComment in italics is used here to indicate block comment style. InlineComment in italics is used here to indicate inline comment style.
LanguageIn-line commentBlock commentAda, Eiffel, Euphoria, Occam, SPARK, ANSI SQL, ToolBook OpenScript, and VHDL-- InlineComment ALGOL 60 comment BlockComment;ALGOL 68 ¢ BlockComment ¢comment BlockComment commentco BlockComment co# BlockComment #£ BlockComment £
AppleScript-- InlineComment(* BlockComment *)Assembly language (varies); InlineComment one example (most assembly languages use line comments only) AutoHotkey; InlineComment/* BlockComment */AWK, Bash, Bourne shell, C shell, Maple, Python, R, Tcl, and Windows PowerShell# InlineComment<# BlockComment #>BASIC (various dialects):'InlineComment (not all dialects)REM InlineComment
C (K&R, ANSI/C89/C90), CHILL, PL/I, and REXX /* BlockComment */C (C99), C++, Go, and JavaScript// InlineComment/* BlockComment */C#// InlineComment/// InlineComment (XML documentation comment)/* BlockComment *//** BlockComment */ (XML documentation comment)CobolInlineComment (when * is in column 7) Curl|| InlineComment|# BlockComment #||foo# BlockComment #|
Cobra# InlineComment/# BlockComment #/ (nestable)D// InlineComment/// Documentation InlineComment (ddoc comments)/* BlockComment *//** Documentation BlockComment */ (ddoc comments)/+ BlockComment +/ (nestable)/++ Documentation BlockComment +/ (nestable, ddoc comments)
DCL$! InlineComment ECMAScript (JavaScript, ActionScript, etc.)// InlineComment/* BlockComment */Forth\ InlineComment( BlockComment ) (single line only)( before -- after ) stack comment convention
FORTRAN 66/77C InlineComment (the letter 'C' in the first column makes the entire line a comment). Fortran 90! InlineComment (all characters on the line, from the exclamation mark onwards, are comments) Haskell-- InlineComment{- BlockComment -}Java// InlineComment/* BlockComment *//** BlockComment */ (Javadoc documentation comment)
Lisp and Scheme; InlineComment#| BlockComment |#Lua-- InlineComment--[==[ BlockComment]==] (variable number of = signs)Maple# InlineComment(* BlockComment *)Mathematica % (* BlockComment *)Matlab% InlineComment%{BlockComment (nestable)%}Note: Both percent–bracket symbols must be the only non-whitespace characters on their respective lines.Object Pascal (Delphi)// InlineComment(* BlockComment *){ BlockComment }OCaml (* BlockComment (* nestable *) *)Pascal, Modula-2, Modula-3, Oberon, and ML: (* BlockComment *) (OCaml comments are nestable)Perl and Ruby# InlineComment=beginBlockComment=cut (POD documentation comment)__END__Comments after end of code
PHP# InlineComment// InlineComment/* BlockComment *//** Documentation BlockComment */ (PHP Doc comments)PILOTR:InlineComment PL/SQL and TSQL-- InlineComment/* BlockComment */REALbasic' InlineComment// InlineCommentrem InlineComment SAS * BlockComment;/* BlockComment */Seed7# InlineComment(* BlockComment *)Simula comment BlockComment;! BlockComment;Smalltalk "BlockComment"Smarty {* BlockComment *}Standard ML (* BlockComment *)TeX, LaTeX, PostScript, Erlang, and S-Lang% InlineComment Texinfo@c InlineComment@comment InlineComment
TUTOR* InlineCommentcommand $$ InlineComment Visual Basic' InlineCommentRem InlineComment Visual Basic .NET' InlineComment''' InlineComment (XML documentation comment)Rem InlineComment
Visual Prolog% InlineComment/* BlockComment */
参考推荐：
Comparison of programming languages (syntax) （wiki）