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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
gmi

Test String

Code Generator

Generated Code

const regex = new RegExp('(aS)\\s+((\\`)?\\w+(\\`)?)(\\s+|\\,|(FRom\\s+))', 'gmi') const str = ` SELECT a.WORKORDER_NO AS workOrderNo, a.ORD_TYPE AS ordType, a.ORD_NO AS ordNo, a.RETURN_FLAG AS returnFlag, a.AREA_ID AS areaId, a.USER_NAME AS userName, a.ADDR_DETAIL AS addrDetail, a.HANDLE_STAFF_ID AS handleStaffId, a.TAKE_STAFF_ID AS takeStaffId, a.TAKE_TS AS takeTs, a.RETURN_STAFF_ID AS returnStaffId, a.RETURN_TS AS returnTs, a.SUMMARY AS summary, a.WO_TITLE AS woTitle, a.INSTALL_FLAG AS installFlag, a.START_TS AS startTs, a.END_TS AS endTs, a.GRID_ID AS gridId, a.SCHEMA_ID AS schemaId, a.PROJECT_ID AS projectId, a.COMMENTS AS comments, a.STATE AS \`state\`, a.CREATE_USER AS createUser, a.CREATE_DATE AS createDate, a.MODIFY_USER AS modifyUser, a.MODIFY_DATE AS modifyDate, a.HANDLE_TEAM_ID AS handleTeamId, a.PACKAGE_ID AS packageId, a.PACKAGE_NAME AS packageName, a.SUB_TYPE AS subType, a.pre_work_order_no AS preWorkOrderNo, a.IS_SYNC AS isSync, a.IS_VIRTUAL AS isVirtual, a.VIRTUAL_WORKORDER_NO AS virtualWorkOrderNo, a.VIRTUAL_WORKORDER_RES_ID AS virtualWorkOrderResId, a.IS_POLE AS isPole, a.VER_NO AS verNo, a.TASK_ID AS taskId, b.USER_NAME AS userName FROM oss_edn.edn_work_order a LEFT JOIN oss_wfm.wfs_user_infor b ON a.HANDLE_STAFF_ID = b.USER_ID WHERE a.WORKORDER_NO = :workOrderNo`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions