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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<div\s+id=""lark-mail-quote-[^<>]+>"; string input = @"<div style=""list-style-position: inside; margin-top: 16px;"" id=""lark-mail-quote-164500864"" class=""quote1645084723054 quoteRendered""><div class=""adit-html-block adit-html-block--collapsed""><div style=""width: 100%; height: 1px; margin-top: 16px; padding-top: 16px; border-top-width: 1px; border-top-style: solid; border-top-color: rgb(222, 224, 227); display: none;"" id=""quote-divider-line""></div><div><div style=""color:rgb(143, 149, 158)"" class=""adit-html-block__attr""><div id=""lark-mail-quote-1013dab007b34a9dc6d40d1f3df7deaa"" class=""quoteRendered""><div id=""lark-mail-quote-6f7b0bbbbcdd7c4219b05c0fd16606c1"" class=""quoteRendered""><div style=""padding-bottom:8px;word-break:break-word;color:#8F959E !important""><div style=""color:#8F959E !important""><span style=""color:#646A73"">发件人：</span><span style=""white-space:normal"">""蓝灿荣""&lt;<a style=""overflow-wrap:break-word;white-space:pre-wrap;hyphens:auto;word-break:break-word;cursor:pointer;text-decoration:none;color:unset"" href=""mailto:lancanrong@bytedance.com"" rel=""nofollow noopener noreferrer"">lancanrong@bytedance.com</a>&gt;</span></div><div style=""color:#8F959E !important""><span style=""color:#646A73"">时间：</span> 2022年2月16日 (周三) 18:50</div><div style=""color:#8F959E !important""><span style=""color:#646A73"">主题：</span> 回复：[External] 测试邮件引用-新旧新旧</div><div style=""color:#8F959E !important""><span style=""color:#646A73"">收件人：</span><span style=""white-space:normal"">""lancanrong""&lt;<a style=""overflow-wrap:break-word;white-space:pre-wrap;hyphens:auto;word-break:break-word;cursor:pointer;text-decoration:none;color:unset"" href=""mailto:lancanrong1@zijietiaodongs.top"" rel=""nofollow noopener noreferrer"">lancanrong1@zijietiaodongs.top</a>&gt;</span></div></div></div></div></div><div style=""margin-top:8px""><div><div><div style=""line-height:1.6;font-size:0.875rem""><div dir=""auto"" class=""><span>444444444444444444444444444444444444</span></div><div id=""lark-mail-quote-164500862"" style=""padding-left:12px;border-left:0.5px solid rgb(187,191,196)"" class=""quoteRendered""><div><blockquote style=""padding:0px;margin:0px"" id=""lark-mail-block-content-164500862"" class=""><div id=""lark-mail-quote-35f365c7aff801f9d443621343497d1c"" class=""quoteRendered""><div id=""lark-mail-quote-07788d8c442dc2ee4e026d9ae58bddfa"" class=""quoteRendered""><div style=""color:rgb(143,149,158)"" id=""lark-mail-block-attr-164500862"" class="">于2022年2月16日 (周三) 18:50 &lt;<a style=""color:rgb(51,112,255)"" href=""mailto:lancanrong1@zijietiaodongs.top"" rel=""nofollow noopener noreferrer"">lancanrong1@zijietiaodongs.top</a>&gt; 写道:</div><blockquote id=""lark-mail-block-content-164500862"" class="" style=""padding:0px;margin:8px 0px 0px""><div><div style=""white-space:pre-wrap;white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6"">333333333333333333333333333333333333333333333333333 </div><div id=""lark-mail-quote-164500860"" style=""list-style-position:inside;margin-top:12px"" class=""quoteRendered""><div class=""adit-html-block adit-html-block--collapsed""><div style=""width:100%;height:1px;margin-top:16px;padding-top:16px;border-top-width:1px;border-top-style:solid;border-top-color:rgb(222,224,227)""></div><div><div id=""lark-mail-block-attr-164500862"" class="" style=""color:rgb(143,149,158)""><div style=""margin-top:12px"" id=""lark-mail-quote-5713ee9ef8fa0880a0db5aca669dc892"" class=""quoteRendered""><div style=""margin-top:12px"" id=""lark-mail-quote-1a8ef6be06d3729d44846305e872806d"" class=""quoteRendered""><div style=""padding-bottom:8px;word-break:break-word;color:#8f959e!important""><div style=""color:#8f959e!important""><span style=""color:#646a73"">发件人：</span><span style=""white-space:normal"">""蓝灿荣""&lt;<a href=""mailto:lancanrong@bytedance.com"" style=""white-space:pre-wrap;word-break:break-word;text-decoration:none;color:rgb(51,112,255)"" rel=""nofollow noopener noreferrer"">lancanrong@bytedance.com</a>&gt;</span></div><div style=""color:#8f959e!important""><span style=""color:#646a73"">时间：</span> 2022年2月16日 (周三) 18:49</div><div style=""color:#8f959e!important""><span style=""color:#646a73"">主题：</span> 回复：[External] 测试邮件引用-新旧新旧</div><div style=""color:#8f959e!important""><span style=""color:#646a73"">收件人：</span><span style=""white-space:normal"">""lancanrong""&lt;<a href=""mailto:lancanrong1@zijietiaodongs.top"" style=""white-space:pre-wrap;word-break:break-word;text-decoration:none;color:unset"" rel=""nofollow noopener noreferrer"">lancanrong1@zijietiaodongs.top</a>&gt;</span></div></div></div></div></div><div style=""margin-top:8px""><div><div><div style=""line-height:1.6;font-size:0.875rem""><div class="" dir=""auto""><span>22222222222222222222222222222222222222222222222222222</span></div><div class=""quoteRendered"" style=""padding-left:12px;border-left:0.5px solid rgb(187,191,196);margin-top:12px"" id=""lark-mail-quote-164500858""><div><blockquote class="" id=""lark-mail-block-content-164500858"" style=""padding:0px;margin:0px""><div style=""margin-top:12px"" id=""lark-mail-quote-f9f9c5db21625596a309d374d3cbde00"" class=""quoteRendered""><div style=""margin-top:12px"" id=""lark-mail-quote-c697014ae5f2a77a28ee6d25e2e4be6e"" class=""quoteRendered""><div class="" id=""lark-mail-block-attr-164500858"" style=""color:rgb(143,149,158)"">于2022年2月16日 (周三) 18:49 &lt;<a href=""mailto:lancanrong1@zijietiaodongs.top"" style=""color:rgb(51,112,255)"" rel=""nofollow noopener noreferrer"">lancanrong1@zijietiaodongs.top</a>&gt; 写道:</div><blockquote style=""padding:0px;margin:8px 0px 0px"" class="" id=""lark-mail-block-content-164500858""><div><div style=""white-space:pre-wrap;white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6"">111111111111111111111111111 </div><div style=""white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6;text-align:left""><img data-realheight=""280"" data-realwidth=""280"" style=""max-width: 100%; height: auto; max-height: none;"" src=""cid:3881ACB5-1580-41CA-8098-38694DB9774E_msgTokenboxcnMHsyNi36OGbKUMVR0WQRCc"" loading=""cid:3881ACB5-1580-41CA-8098-38694DB9774E_msgTokenboxcnMHsyNi36OGbKUMVR0WQRCc""></div><div></div><div> 顶顶顶顶顶顶顶顶</div><div> 撒发达分的的撒打发灌灌灌灌灌灌灌灌</div><div style=""white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6""></div></div></blockquote></div></div></blockquote></div></div></div></div></div></div></div></div></div><div style=""white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6;text-align:left""><img src=""cid:3881ACB5-1580-41CA-8098-38694DB9774E_msgTokenboxcnMHsyNi36OGbKUMVR0WQRCc"" style=""max-width: 100%; height: auto; max-height: none;"" loading=""cid:3881ACB5-1580-41CA-8098-38694DB9774E_msgTokenboxcnMHsyNi36OGbKUMVR0WQRCc""><img data-realheight=""320"" data-realwidth=""920"" width=""474"" src=""cid:6a880d43-3e11-4f9e-b0d7-1ed8c7dd4bad_msgTokenboxcnPkvwAxHFdjiDRi0YSSalIh"" style=""max-width: 100%; height: auto; max-height: none;"" loading=""cid:6a880d43-3e11-4f9e-b0d7-1ed8c7dd4bad_msgTokenboxcnPkvwAxHFdjiDRi0YSSalIh""></div><div> 顶顶顶顶顶顶顶顶</div><div> 撒发达分的的撒打发灌灌灌灌灌灌灌灌</div><div style=""white-space:pre-wrap;margin-top:4px;margin-bottom:4px;line-height:1.6""></div></div></blockquote></div></div></blockquote></div></div></div></div></div></div></div></div></div>"; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx