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
Processing...

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<\\{if \\$data\\.nowPage>1\\}>.*?</div>\\R*<\\{/if\\}>"; final String string = "\n" + " \n\n" + "I'm looking for a regular expression to delete htmlA. The border start from\n\n" + "<{if $data.nowPage>1}> to /div> 1 breakLine <{/if}>\n\n" + "htmlA\n\n" + "<{if $data.nowPage>1}>\n" + "<div class=\"pageArrow pageFirst\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=1\"><span class=\"icon arrow-first\"></span></a></div>\n" + "<div class=\"pageArrow pagePrev\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=<{$data.nowPage-1}>\"><span class=\"icon arrow-left\"></span></a></div>\n" + "<{/if}>\n\n" + "I have tried\n\n" + "$fullHtml = readFileData($file);\n" + "preg_match(\"/(<{if \\\\\\$data\\.nowPage>1}>(.*?)<\\/div>)(\\s)(.+?)<{\\/if}>/si\",$fullHtml,$htmlA);\n" + "//$fullHtml = preg_replace(...,'',$fullHtml);\n\n" + "but it stopped too early and why print_r($htmlA) shows 5 keys?\n\n" + "Array\n" + "(\n" + " [0] => <{if $data.nowPage>1}>\n" + " <div class=\"pageArrow pageFirst\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=1\"><span class=\"icon arrow-first\"></span></a></div>\n" + " <div class=\"pageArrow pagePrev\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}>\n" + " [1] => <{if $data.nowPage>1}>\n" + " <div class=\"pageArrow pageFirst\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=1\"><span class=\"icon arrow-first\"></span></a></div>\n" + " [2] => \n" + " <div class=\"pageArrow pageFirst\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=1\"><span class=\"icon arrow-first\"></span></a>\n" + " [3] => \n" + " [4] => \n" + " <div class=\"pageArrow pagePrev\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}>\n" + ")\n\n" + "fullHtml. line3 to line6.\n\n" + "<div class=\"pageContainer\">\n" + " <div class=\"pageBox\">\n" + " <{if $data.nowPage>1}>\n" + " <div class=\"pageArrow pageFirst\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=1\"><span class=\"icon arrow-first\"></span></a></div>\n" + " <div class=\"pageArrow pagePrev\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=<{$data.nowPage-1}>\"><span class=\"icon arrow-left\"></span></a></div>\n" + " <{/if}>\n\n" + " <{for $i=$data.nowPage-$data.pageFit to $data.totalPage}>\n\n" + " <{if $data.nowPage == ($i)}>\n" + " <div class=\"pageBtn active\"><a href=\"javascript:void(0);\"><{$i}></a></div>\n" + " <{else if $i>($data.nowPage+$data.pageFit)}>\n" + " <div class=\"pageMore\"><span class=\"icon moreIcon\"></span></div>\n" + " <{break}>\n" + " <{else if $i>0}>\n" + " <{if $i==$data.nowPage-$data.pageFit && $i>1}>\n" + " <div class=\"pageMore\"><span class=\"icon moreIcon\"></span></div>\n" + " <{/if}>\n" + " <div class=\"pageBtn\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=<{$i}>\"><{$i}></a></div>\n" + " <{else}>\n" + " <{/if}>\n\n" + " <{/for}>\n\n" + " <{if $data.nowPage<$data.totalPage}>\n" + " <div class=\"pageArrow pageNext\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=<{$data.nowPage+1}>\"><span class=\"icon arrow-right\"></span></a></div>\n" + " <div class=\"pageArrow pageLast\"><a href=\"?<{if !empty($data.years)}>y=<{$data.years}><{/if}><{if !empty($data.month)}>&m=<{$data.month}><{/if}>&p=<{$data.totalPage}>\"><span class=\"icon arrow-last\"></span></a></div>\n" + " <{/if}>\n" + " </div>\n" + "</div>"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.DOTALL); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html