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

$re = '/(?<metric>.*)(?<fields>:{.*})? (?<value>.*)/m'; $str = 'jvm_buffer_memory_used_bytes{id="direct",} 81920.0 jvm_buffer_memory_used_bytes{id="mapped",} 0.0 jvm_threads_live 23.0 tomcat_global_received_bytes_total{name=" http - nio -8080",} 0.0 tomcat_global_received_bytes_total{name="http-nio-8080",} 0.0 jvm_gc_pause_seconds_count{action="end of minor GC",cause="Allocation Failure",} 7.0 jvm_gc_pause_seconds_sum{action="end of minor GC",cause="Allocation Failure",} 0.232 jvm_gc_pause_seconds_count{action="end of minor GC",cause="Metadata GC Threshold",} 1.0 jvm_gc_pause_seconds_sum{action="end of minor GC",cause="Metadata GC Threshold",} 0.01 jvm_gc_pause_seconds_count{action="end of major GC",cause="Metadata GC Threshold",} 1.0 jvm_gc_pause_seconds_sum{action="end of major GC",cause="Metadata GC Threshold",} 0.302 jvm_gc_pause_seconds_max{action="end of minor GC",cause="Allocation Failure",} 0.0 jvm_gc_pause_seconds_max{action="end of minor GC",cause="Metadata GC Threshold",} 0.0 jvm_gc_pause_seconds_max{action="end of major GC",cause="Metadata GC Threshold",} 0.0 jvm_gc_live_data_size_bytes 5.0657472E7'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php