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

import Foundation let pattern = #"(?:AzureFirewallNetworkRule|AzureFirewallApplicationRule).*?(?<=to\s)(?<dest>[^(?:\.\s)].*)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" {"category": "AzureFirewallNetworkRule", "time": "2023-03-29T20:00:53.4378840Z", "resourceId": "/SUBSCRIPTIONS/CA41E67C-1C2F-47D5-9252-402EDF21E20F/RESOURCEGROUPS/RG-PROD-CONNECTIVITY-EUS2/PROVIDERS/MICROSOFT.NETWORK/AZUREFIREWALLS/AZFW-HUB-PROD-EUS2", "operationName": "AzureFirewallNetworkRuleLog", "properties": {"msg": "ICMP Type=8 request from 10.0.2.5 to 10.252.0.133. Action: Allow. Policy: afwp-hub-prod-eus2. Rule Collection Group: global. Rule Collection: Allowed-Network-Rules. Rule: QuadToAzurePing"}} {"category": "AzureFirewallNetworkRule", "time": "2023-03-29T19:54:03.8947510Z", "resourceId": "/SUBSCRIPTIONS/CA41E67C-1C2F-47D5-9252-402EDF21E20F/RESOURCEGROUPS/RG-PROD-CONNECTIVITY-EUS2/PROVIDERS/MICROSOFT.NETWORK/AZUREFIREWALLS/AZFW-HUB-PROD-EUS2", "operationName": "AzureFirewallNetworkRuleLog", "properties": {"msg": "TCP request from 10.252.0.158:50458 to 161.49.232.168:10002. Action: Allow. Policy: afwp-hub-prod-eus2. Rule Collection Group: global. Rule Collection: Allowed-Network-Rules. Rule: AzureToQuadInternalF5"}} {"category": "AzureFirewallApplicationRule", "time": "2023-03-29T14:46:55.5760760Z", "resourceId": "/SUBSCRIPTIONS/CA41E67C-1C2F-47D5-9252-402EDF21E20F/RESOURCEGROUPS/RG-PROD-CONNECTIVITY-EUS2/PROVIDERS/MICROSOFT.NETWORK/AZUREFIREWALLS/AZFW-HUB-PROD-EUS2", "operationName": "AzureFirewallApplicationRuleLog", "properties": {"msg": "HTTPS request from 10.252.0.158:50868 to login.microsoftonline.com:443. Action: Allow. Policy: afwp-hub-prod-eus2. Rule Collection Group: global. Rule Collection: Allowed-Application-Rules. Rule: AzureAD"}} {"category": "AzureFirewallApplicationRule", "time": "2023-03-29T20:50:13.0977850Z", "resourceId": "/SUBSCRIPTIONS/CA41E67C-1C2F-47D5-9252-402EDF21E20F/RESOURCEGROUPS/RG-PROD-CONNECTIVITY-EUS2/PROVIDERS/MICROSOFT.NETWORK/AZUREFIREWALLS/AZFW-HUB-PROD-EUS2", "operationName": "AzureFirewallApplicationRuleLog", "properties": {"msg": "HTTP request from 10.252.0.158:50039 to google.com:80. Action: Deny. No rule matched. Proceeding with default action"}} """# 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: https://developer.apple.com/documentation/foundation/nsregularexpression