Regular Expressions 101

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  • 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
  • A single character of: a, b, c or d
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Character class intersection
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression
No Match


Test String

Code Generator

Generated Code

import Foundation let pattern = #"(aS)\s+((\`)?\w+(\`)?)(\s+|\,|(FRom\s+))"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive]) let testString = #""" 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 """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(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 Swift 5.2, please visit: