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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?s-i)(<User>\s*USER_NAME\s*<\/User>.*?<Password>\s*)(\S+)(\s*<\/Password>)/m'; $str = ' <Connection type="Teradata" autoCommit="True"> <Path>Teradata\\BEDW - USER_NAME1</Path> <AutoConnect>False</AutoConnect> <DefaultOnStartup>False</DefaultOnStartup> <Database> </Database> <Host>teraprd2.ca.host.com</Host> <User>USER_NAME1</User> <Category>F00000FF:Production</Category> <Password>ENCRYPTED_PWD1</Password> <WinAuth>False</WinAuth> <LastConnectionDate>2019-09-11T16:32:09.1945969</LastConnectionDate> <SessionMode>Teradata</SessionMode> <SessionCharacterSet>UTF16</SessionCharacterSet> <PortNumber>1025</PortNumber> <DataEncryption>False</DataEncryption> <ResponseBufferSize>1040000</ResponseBufferSize> </Connection> </Connections> <Groups /> </Group> <Group name="EFBI - USER_NAME" description=""> <Path>Teradata</Path> <Connections> <Connection type="Teradata" autoCommit="True"> <Name>USER_NAME @TERADEVL (EFBI_DEV1_USAGE_METRICS_B)</Name> <Path>Teradata\\EFBI - USER_NAME</Path> <AutoConnect>False</AutoConnect> <DefaultOnStartup>False</DefaultOnStartup> <Database>EFBI_DEV1_USAGE_METRICS_B</Database> <Host>teradevl.ca.host.com</Host> <User>USER_NAME</User> <Category>BCCF87FF:Development</Category> <Password>ENCRYPTED_PWD2</Password> <WinAuth>False</WinAuth> <LastConnectionDate>2019-04-30T15:41:31.3601044</LastConnectionDate> <SessionMode>Teradata</SessionMode> <SessionCharacterSet>UTF16</SessionCharacterSet> <PortNumber>1025</PortNumber> <DataEncryption>False</DataEncryption> <DefaultDatabase>EFBI_DEV1_USAGE_METRICS_B</DefaultDatabase> <ResponseBufferSize>1040000</ResponseBufferSize> </Connection> '; $subst = "$1(NEW_ENCRYPTED_PWD)$3"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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