正则表达式常用内容

常用元字符

.匹配除换行符以外的任意字符\w匹配字母或数字或下划线或汉字\s匹配任意空白字符\d匹配数字\b匹配单词的开始或结束^匹配字符串的开始$匹配字符串的结束

常用限定符

*重复零次或多次+重复一次或多次?重复零次或一次{n}重复n次{n,}重复n次或更多次{n,m}重复n-m次

通配符(.)

使用"."可以匹配任何字符，如果要匹配"."本身，那么需要使用转义字符来取消"."的特殊意义，如"." 来匹配"."

Task    Text     
Match    cat.    Success
Match    896.    Success
Match    ?=+.    Success
Skip    abc1

Pattern: ...\.

匹配特定字符

使用"[]"可以将需要匹配的特定字符放在方括号中进行匹配，如：只匹配a,b,c，那么可写成[abc]

Task    Text     
Match    can    Success
Match    man    Success
Match    fan    Success
Skip    dan    To be completed
Skip    ran    To be completed
Skip    pan

Pattern: [cmf]an

排除特定字符

使用方法和上面的"[]"类似，只是在字符前加上""，以表示之后的这些字符是排除匹配的。如：[abc]表示除了a,b,c之外的任何字符都可以进行匹配。

Task    Text     
Match    hog    Success
Match    dog    Success
Skip    bog

Pattern: [^b]og

字符范围

如果要匹配的字符太多，那我们并不需要将所有字符都像上面一样全部列出来，只需用"-"将范围表示出来。[0-6]表示只匹配0-6的数字，[^n-p]表示不匹配n-p的任何字符。"\w"等价于[A-Za-z0-9_]

Task    Text     
Match    Ana    Success
Match    Bob    Success
Match    Cpc    Success
Skip    aax    To be completed
Skip    bby    To be completed
Skip    ccz

Pattern: [A-C]

重复

如果我们要匹配的相同字符有好几个，使用"\w\w\w"就显得有点麻烦，所以可以通过下面这种方法来匹配多个字符的情况，如：有3个"a"要匹配，则直接用a{3}表示即可。a{1,3}重复1-3次，[wxy]{5}，w/x/y 任意一个字符重复5次，.{2-6}则表示任意字符重复2-6次

Task    Text     
Match    wazzzzzup    Success
Match    wazzzup    Success
Skip    wazup

Pattern: waz{2}

"*": 重复0次或者多次 "+": 重复1次或者多次

Task    Text     
Match    aaaabcc    Success
Match    aabbbbc    Success
Match    aacc    Success
Skip    a

Pattern: a*b*c+

"?": 重复零次或一次

Task    Text     
Match    1 file found?    Success
Match    2 files found?    Success
Match    24 files found?    Success
Skip    No files found.    To be completed

Pattern: [0-9]+ files? found\?

匹配空白符

"\s" 可以匹配任意的空白符

Task    Text     
Match    1.   abc    Success
Match    2.    abc    Success
Match    3.           abc    Success
Skip    4.abc    To be completed

Pattern: \d\.\s+abc

匹配行起始/结束字符

"^": ^abc 匹配以abc开头的字符 "$": abc$ 匹配以abc结束的字符

Task    Text     
Match    Mission: successful    Success
Skip    Last Mission: unsuccessful    To be completed
Skip    Next Mission: successful upon capture of target    To be completed

Pattern: ^Mission:

匹配组

"()" 将要匹配的内容放在()中

Task    Text    Capture Groups     
Capture    file_record_transcript.pdf    file_record_transcript    Success
Capture    file_07241999.pdf    file_07241999    Success
Skip    testfile_fake.pdf.tmp        To be completed

Pattern: ^(file_\w+)

嵌套分组

"(())" 将多个组进行嵌套匹配

Task    　　Text    Capture Groups     
Capture    Jan 1987    Jan 1987 1987    Success
Capture    May 1969    May 1969 1969    Success
Capture    Aug 2011    Aug 2011 2011    Success

Pattern： ^(\w+\s(\d+))

多个分组组合

Task　　　　Text　　　　Capture GroupsCapture    1280x720    1280 720    Success
Capture    1920x1600    1920 1600    Success
Capture    1024x768    1024 768    Success

Pattern: (\d+)\w(\d+)

增加可读性

Task    Text     
Match    I love cats    Success
Match    I love dogs    Success
Skip    I love logs    To be completed
Skip    I love cogs

Pattern: I love (cats|dogs)
Pattern: ([cd]ats*|[dh]ogs?)

练习

Task    Text     
Match    3.14529    Success
Match    -255.34    Success
Match    128    Success
Match    1.9e10    Success
Match    123,340.00    Success
Skip    720p    To be completed

Pattern: ^-?\d+(,\d+)*(\.\d+(e\d+)?)?$
Capture    415-555-1234    415    Success
Capture    650-555-2345    650    Success
Capture    (416)555-3456    416    Success
Capture    202 555 4567    202    Success
Capture    4035555678    403    Success
Capture    1 416 555 9292    416    Success

Pattern: 1?\s?\(?(\d{3})\)?[\s-]?\d{3}[\s-]?\d{4}
Task    Text    Capture Groups     
Capture    [email protected]    tom    Success
Capture    [email protected]    tom.riddle    Success
Capture    [email protected]    tom.riddle    Success
Capture    [email protected]    tom    Success
Capture    [email protected]    potter    Success
Capture    [email protected]    harry    Success
Capture    [email protected]    hermione    Success

Pattern: ^([\w\.]*)
Task    Text    Capture Groups     
Capture    <a>This is a link</a>    a    Success
Capture    <a href='https://regexone.com'>Link</a>    a    Success
Capture    <div class='test_style'>Test</div>    div    Success
Capture    <div>Hello <span>world</div>    div    Success

Pattern: <(\w+)*
Task    Text    Capture Groups     
Skip    .bash_profile        To be completed
Skip    workspace.doc        To be completed
Capture    img0912.jpg    img0912 jpg    Success
Capture    updated_img0912.png    updated_img0912 png    Success
Skip    documentation.html        To be completed
Capture    favicon.gif    favicon gif    Success
Skip    img0912.jpg.tmp        To be completed
Skip    access.lock        To be completed

Pattern: (\w+)(\.)(jpg|png|gif)$
Task    Text    Capture Groups     
Capture                The quick brown fox...    The quick brown fox...    Success
Capture       jumps over the lazy dog.    jumps over the lazy dog.    Success

Pattern: ^\s*(.*)\s*$
Task    Text    Capture Groups     
Skip    W/dalvikvm( 1553): threadid=1: uncaught exception        To be completed
Skip    E/( 1553): FATAL EXCEPTION: main        To be completed
Skip    E/( 1553): java.lang.StringIndexOutOfBoundsException        To be completed
Capture    E/( 1553):   at widget.List.makeView(ListView.java:1727)    makeView ListView.java 1727    Success
Capture    E/( 1553):   at widget.List.fillDown(ListView.java:652)    fillDown ListView.java 652    Success
Capture    E/( 1553):   at widget.List.fillFrom(ListView.java:709)    fillFrom ListView.java 709    Success

Pattern: \.+(\w+)+\((\w+\.\w+)+:(\d+)\)
Pattern: (\w+)\(([\w\.]+):(\d+)\)
Task    Text    Capture Groups     
Capture    ftp://file_server.com:21/top_secret/life_changing_plans.pdf    ftp file_server.com 21    Success
Capture    https://regexone.com/lesson/introduction#section    https regexone.com    Success
Capture    file://localhost:4040/zip_file    file localhost 4040    Success
Capture    https://s3cur3-server.com:9999/    https s3cur3-server.com 9999    Success
Capture    market://search/angry%20birds    market search    Success

Pattern: (\w+)://([\w\.-]+)(:(\d+))?