Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

`
`
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?s:("name" : "(.*?)".*?作者[:]*</span>[:]*.*?>(.*?)<.*?出版社.*?> (.*?)<.*?>出版年.*?([\d]{4}-[\d]).*?定价:</span> (.*?)<.*?ISBN:</span> (.*?)<.*?v:average"> ([\d].[\d]).*?v:votes">([\d]+?)<.*?"rating_per">(.*?)<.*?"rating_per">(.*?)<.*?"rating_per">(.*?)<.*?"rating_per">(.*?)<.*?"rating_per">(.*?)<))`) var str = ` <script type="application/ld+json"> { "@context":"http://schema.org", "@type":"Book", "workExample": [], "name" : "索拉里斯星", <span class="pl"> 作者</span>: <a class="" href="/search/%E6%96%AF%E5%9D%A6%E5%B0%BC%E6%96%AF%E7%93%A6%E5%A4%AB%C2%B7%E8%8E%B1%E5%A7%86">[波] 斯坦尼斯瓦夫·莱姆</a> </span><br/> <span class="pl">出版社:</span> 译林出版社<br/> <span class="pl">原作名:</span> Solaris<br/> <span> <span class="pl"> 译者</span>: <a class="" href="/search/%E9%9D%96%E6%8C%AF%E5%BF%A0">靖振忠</a> </span><br/> <span class="pl">出版年:</span> 2021-8<br/> <span class="pl">页数:</span> 254<br/> <span class="pl">定价:</span> 49.00元<br/> <span class="pl">装帧:</span> 平装<br/> <span class="pl">丛书:</span>&nbsp;<a href="https://book.douban.com/series/54333">译林幻系列</a><br> <span class="pl">ISBN:</span> 9787544782173<br/> </div> </div> <div id="interest_sectl" class=""> <div class="rating_wrap clearbox" rel="v:rating"> <div class="rating_logo">豆瓣评分</div> <div class="rating_self clearfix" typeof="v:Rating"> <strong class="ll rating_num " property="v:average"> 8.7 </strong> <span property="v:best" content="10.0"></span> <div class="rating_right "> <div class="ll bigstar45"></div> <div class="rating_sum"> <span class=""> <a href="comments" class="rating_people"><span property="v:votes">8085</span>人评价</a> </span> </div> </div> </div> <span class="stars5 starstop" title="力荐"> 5星 </span> <div class="power" style="width:64px"></div> <span class="rating_per">46.0%</span> <br> <span class="stars4 starstop" title="推荐"> 4星 </span> <div class="power" style="width:54px"></div> <span class="rating_per">39.4%</span> <br> <span class="stars3 starstop" title="还行"> 3星 </span> <div class="power" style="width:17px"></div> <span class="rating_per">12.5%</span> <br> <span class="stars2 starstop" title="较差"> 2星 </span> <div class="power" style="width:2px"></div> <span class="rating_per">1.8%</span> <br> <span class="stars1 starstop" title="很差"> 1星 </span> <div class="power" style="width:0px"></div> <span class="rating_per">0.3%</span> ` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/