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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?:^|[^%])(?:%%)*(%(?:\d+\$)?(?:\+)?(?:0|'.)?(?:\-)?(?:\d+)?(?:\.\d+)?[bcdeEufFgGosxX])"; string input = @"<?php $n = 43951789; $u = -43951789; $c = 65; // ASCII コードの 65 は 'A' です // %% に注目しましょう。これは、リテラル '%' を文字として出力します printf(""%%b = '%b'\n"", $n); // 2 進表現 printf(""%%c = '%c'\n"", $c); // ascii 文字を表示します。chr() 関数と同じです printf(""%%d = '%d'\n"", $n); // 標準の整数表現 printf(""%%e = '%e'\n"", $n); // 科学記法 printf(""%%u = '%u'\n"", $n); // 正の整数の、符号なし整数表現 printf(""%%u = '%u'\n"", $u); // 負の整数の、符号なし整数表現 printf(""%%f = '%f'\n"", $n); // 浮動小数点表現 printf(""%%o = '%o'\n"", $n); // 8 進表現 printf(""%%s = '%s'\n"", $n); // 文字列表現 printf(""%%x = '%x'\n"", $n); // 16 進表現 (小文字) printf(""%%X = '%X'\n"", $n); // 16 進表現 (大文字) printf(""%%+d = '%+d'\n"", $n); // 正の整数に符号指定子を使用 printf(""%%+d = '%+d'\n"", $u); // 負の整数に符号指定子を使用 ?> <?php $s = 'monkey'; $t = 'many monkeys'; printf(""[%s]\n"", $s); // 標準の文字列出力 printf(""[%10s]\n"", $s); // 空白を使用して右詰め printf(""[%-10s]\n"", $s); // 空白を使用して左詰め printf(""[%010s]\n"", $s); // ゼロ埋めは文字列でも可能です printf(""[%'#10s]\n"", $s); // ゼロの代わりに独自の文字 '#' で埋めます printf(""[%10.10s]\n"", $t); // 左詰めを行い、10 文字以上は切り捨てます ?> 例9 sprintf(): 整数のゼロ埋め <?php $isodate = sprintf(""%04d-%02d-%02d"", $year, $month, $day); ?> 例10 sprintf(): 通貨をフォーマットする例 <?php $money1 = 68.75; $money2 = 54.35; $money = $money1 + $money2; // echo $money は ""123.1"" を出力します。 $formatted = sprintf(""%01.2f"", $money); // echo $formatted は ""123.10""を出力します ?> 例11 sprintf(): 科学記法 <?php $number = 362525200; echo sprintf(""%.3e"", $number); // 3.625e+8 を出力します ?> "; 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