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

/
/
g

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"getObj\(""Frm_Logintoken""\).value = ""(.*)"";"; string input = @" <!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd""><html xmlns=""http://www.w3.org/1999/xhtml""> <head> <META HTTP-EQUIV=""pragma"" CONTENT=""no-cache""> <META HTTP-EQUIV=""Cache-Control"" CONTENT=""no-cache, must-revalidate""> <meta http-equiv=""Content-Type"" content=""text/html; charset=iso-8859-1"" /> <title>&#90;&#88;&#72;&#78;&#32;&#72;&#49;&#48;&#56;&#78;&#32;&#86;&#50;&#46;&#53;</title> <LINK REL=""stylesheet"" HREF=""css/login.css"" TYPE=""text/css"" /> <LINK REL=""stylesheet"" HREF=""css/styleen.css"" TYPE=""text/css"" /> <script> function getObj(id) { return(document.getElementById(id)); } var SetTFlag = 0; var maxtime; var interval; function setTime() { if(window.name>=60 || window.name<0 || window.name=="") { maxtime = Math.min(60, 0 + 60 - 218143); } else { maxtime = window.name; } if(maxtime>=0) { seconds = maxtime; getObj(""time"").innerHTML=seconds+"" secs""; if (maxtime == 0) { setDisable(); SetTFlag =0; window.name=""; if(interval) { clearInterval(interval); interval = 0; } } else { --maxtime; SetTFlag = 1; window.name = maxtime; } } } function setinner(type) { if (SetTFlag ==0) { getObj(""myLayer"").style.visibility = type ; } } function Transfer_meaning(id,value) { getObj(id).value=value; } function ChangeLang() { var lang = ""English""; getObj(""_lang"").disabled = false; getObj(""Frm_Username"").disabled = true; getObj(""Frm_Password"").disabled = true; if(true != getObj(""TestLang01"").disabled) { if (""English"" == lang) { getObj(""_lang"").value = ""Chinese""; } else if (""Chinese"" == lang) { getObj(""_lang"").value = ""English""; } getObj(""action"").value = ""setlang""; getObj(""Frm_Username"").disabled = true; getObj(""Frm_Password"").disabled = true; getObj(""LoginId"").disabled = true; document.fLogin.submit(); } } </script> </head> <body> <div id=""container""> <div id=""myLayer"" onmousedown=""setinner('hidden')"" style=""position:absolute; width:185px; height:91px; z-index:9; right: 50px; top: 140px; background: url(img/pop_up.gif) no-repeat; border: 1px none #000000; visibility: hidden;""> <div id=""Layer1"" style=""position:absolute; width:180px; height:45px; z-index:10; left: 2px; top: 28px;""> <table width=""183"" border=""0""> <tr> <td width=""183"">&nbsp;&nbsp;<font id=""errmsg"" class=""notecontent"" ></font><span id=""time"" style=""color:red;display:none;""></span></td> </tr> </table> </div> <div id=""Layer3"" style=""position:absolute; width:140px; height:10px; z-index:11; left: 34px; top: 9px; font-size: 8pt;""> <font class=""note"" id=""errnote"">&nbsp;Error</font> </div> </div> <!--head²¿·Ö¿ªÊ¼--> <div id=""head""> <div class=""type""><font id="">&#90;&#88;&#72;&#78;&#32;&#72;&#49;&#48;&#56;&#78;&#32;&#86;&#50;&#46;&#53;</font></div> <div id=""banner"" style=""background-image:url(img/banner.gif); background-repeat:no-repeat""></div> </div> <!--head²¿·Ö½áÊø--> <!--content²¿·Ö¿ªÊ¼--> <div id=""loginArea""> <form name=""fLogin"" id=""fLogin"" method=""post"" onsubmit=""return false;"" action=""> <input type=""hidden"" name=""_lang"" id=""_lang"" value="" disabled> <input type=""hidden"" name=""frashnum"" id=""frashnum"" value=""> <input type=""hidden"" name=""action"" id=""action"" value=""login""> <input type=""hidden"" name=""Frm_Logintoken"" id=""Frm_Logintoken"" value=""> <!--ÄÚÈÝ¿ªÊ¼--> <div class=""login_frame""> <ul class=""login_title""> <li class=""login_title_left""></li> <li class=""login_title_center"">Please login to continue...</li> <li class=""login_title_right""></li> </ul> <div class=""content login_content""> <ul class=""login_blank""></ul> <ul class=""login_ul_1""> <li class=""login_li_1""><span>Username</span></li> <li class=""login_li_2""> <input type=""text"" class=""username"" name=""Username"" id=""Frm_Username""> </li> </ul> <ul class=""login_blank""></ul> <ul class=""login_ul_1""> <li class=""login_li_1""><span>Password</span></li> <li class=""login_li_2""> <input type=""password"" class=""password"" name=""Password"" id=""Frm_Password""> </li> <li class=""login_li_3""> <input class=""login"" type=""submit"" id=""LoginId"" value=""Login"" onclick=""dosubmit()""> </li> </ul> </div> </div> <!--ÄÚÈݽáÊø--> </form> </div> <!--bottom²¿·Ö¿ªÊ¼--> <div style=""font-family: Arial;font-size: 12px;text-align:center;""> &copy; 2008-2015 ZTE Corporation. All rights reserved </div> <div class=""bottom_line""></div> <div id=""bottomx""></div> <!--bottom²¿·Ö½áÊø--> </div> </body> </html> <script> window.name=""; function SetDisabled() { getObj(""errmsg"").innerHTML = ""You have input the wrong username or password for three times. Please try again a minute later.""; getObj(""Frm_Username"").disabled = true; getObj(""Frm_Password"").disabled = true; getObj(""LoginId"").disabled = true; getObj(""myLayer"").style.visibility = ""visible"" ; getObj(""time"").style.display = "" ; interval = setInterval(""setTime()"",1000); } function setDisable() { if (SetTFlag == 1) { getObj(""Frm_Username"").disabled = false; getObj(""Frm_Password"").disabled = false; getObj(""LoginId"").disabled = false; getObj(""time"").style.display = ""none""; getObj(""myLayer"").style.visibility = ""hidden""; } } function dosubmit() { if (getObj(""Frm_Username"").value == "") { getObj(""errmsg"").innerHTML = ""Username cannot be empty.""; getObj(""myLayer"").style.visibility = ""visible"" ; return; } else { getObj(""LoginId"").disabled = true; getObj(""Frm_Logintoken"").value = ""7""; document.fLogin.submit(); } } </script> "; foreach (Match m in Regex.Matches(input, pattern)) { 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