regex101: PCRE (Legacy) Match Workspace

To:the literal text To: (case sensitive)

Group 1( =\?.*\?= )

=the literal text =

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

.*any character (except for line terminators), repeated any number of times

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

= the literal text =

Group 2(Cc|Subject)

1st AlternativeCc

Ccthe literal text Cc (case sensitive)

2nd AlternativeSubject

Subjectthe literal text Subject (case sensitive)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Search reference

Regular Expression

To:( =\?.*\?= )(Cc|Subject):

New

# Base base
To: =?GB2312?B?s8LR9A==?= , =?GB2312?B?0e7V8buq?= , =?GB2312?B?ts69qNOi?= , =?GB2312?B?wO7RxcX0?= , =?GB2312?B?wfXX07vU?= Cc: =?GB2312?B?wfXA2g==?= , =?GB2312?B?wfW7qNHT?= Subject: =?GB2312?B?u9i4tDogu9i4tDogcGPXqNawvNK9zMrTxrVidWc=?=

# Base base without Cc:
To: =?GB2312?B?s8LR9A==?= , =?GB2312?B?0e7V8buq?= , =?GB2312?B?ts69qNOi?= , =?GB2312?B?wO7RxcX0?= , =?GB2312?B?wfXX07vU?= Subject: =?GB2312?B?u9i4tDogu9i4tDogcGPXqNawvNK9zMrTxrVidWc=?=

# Only one addressee
To: =?GB2312?B?s8LR9A==?= Cc: =?GB2312?B?wfXA2g==?= , =?GB2312?B?wfW7qNHT?= Subject: =?GB2312?B?u9i4tDogu9i4tDogcGPXqNawvNK9zMrTxrVidWc=?=

# Only one addressee without Cc:
To: =?GB2312?B?s8LR9A==?= Subject: =?GB2312?B?u9i4tDogu9i4tDogcGPXqNawvNK9zMrTxrVidWc=?=

Regular Expressions 101

Regular Expression

Substitution