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Topics: regex

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• How to remove duplicate lines with regular expressions

  

  By StevenLevithan : 30 October 2009 - 08:35 AM

  There is a variety of software (including the Unix command-line utility uniq and Windows PowerShell cmdlet Get-Unique) that can help you remove duplicate lines in a file or ...

  Tags:

  • duplicates
  • regex
  • regular expression
  • .NET
  • java
  • javascript
  • PCRE
  • perl
  • python
  • ruby
  • php

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• How to Strip Invalid Characters from Filenames

  

  By Jan Goyvaerts : 13 October 2009 - 11:08 AM

  If you want to strip a string of characters that aren't valid in Windows filenames use the following regular expression to accompish the task. Regular expression[\\/:"*?|]+ Reg...

  Tags:

  • regex
  • invalid characters
  • filenames

  0Votes

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• How to quickly find the last match in a string in C#

  

  By LaurelRuma : 01 October 2009 - 12:10 PM

  You need to find the last pattern match in a string, but you do not want the overhead of finding all matches in a string and having to move to the last match in the collection of matches. To execute ...

  Tags:

  • .net
  • C#
  • regex
  • regular expression

  0Votes

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• How to Match IPv4 Addresses with Regular Expressions

  

  By Jan Goyvaerts : 30 September 2009 - 01:11 PM

  If you want to check whether a certain string represents a valid IPv4 address in 255.255.255.255 notation, try one of these examples from Regular Expressions Cookbook: Simple regex to check fo...

  Tags:

  • python
  • perl
  • javascript
  • java
  • address
  • IPv4
  • regex
  • ruby
  • .Net

  1Vote

  0Comments

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• How to validate URLs with regular expressions

  

  By Jan Goyvaerts : 28 September 2009 - 11:03 AM

  If you want to check whether a given piece of text is a URL that is valid for your purposes, you can try one of the following solutions: Allow almost any URL: ^(https?|ftp|file)://....

  Tags:

  • regex
  • URL
  • validation

  0Votes

  0Comments

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• How to manipulate numbers with thousand separators using regular expressions

  

  By Jan Goyvaerts : 18 September 2009 - 03:55 PM

  If you want to match numbers that use the comma as the thousand separator and the dot as the decimal separator, refer to the following examples: Mandatory integer and fraction:^[0-9]{1,3...

  Tags:

  • regex
  • separators
  • numbers

  0Votes

  0Comments

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• How to validate traditional date formats with regular expressions

  

  By Jan Goyvaerts : 18 September 2009 - 12:45 PM

  If you want to validate dates in the traditional formats mm/dd/yy, mm/dd/yyyy, dd/mm/yy, and dd/mm/yyyy, using a simple regex that simply checks whether the input looks ...

  Tags:

  • ruby
  • python
  • perl
  • PCRE
  • javascript
  • java
  • .Net
  • dates
  • regex

  1Vote

  0Comments

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• How to create regular expression objects

  

  By Jan Goyvaerts : 18 September 2009 - 10:51 AM

  If you want to instantiate a regular expression object or otherwise compile a regular expression so you can use it efficiently throughout your application, try one of t...

  Tags:

  • php
  • perl
  • javascript
  • java
  • vb.net
  • c#
  • objects
  • regex
  • python
  • ruby

  0Votes

  0Comments

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• How to search line by line with a regular expression

  

  By Jan Goyvaerts : 18 September 2009 - 10:22 AM

  Traditional grep tools apply your regular expression to one line of text at a time, and display the lines matched (or not matched) by the regular expression. If you hav...

  Tags:

  • python
  • perl
  • javascript
  • java
  • vb.net
  • c#
  • search
  • regex
  • php
  • ruby

  1Vote

  0Comments

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• How to replace all matches in a regular expression

  

  By Jan Goyvaerts : 18 September 2009 - 09:56 AM

  If you want to replace all matches of the regular exp​ression before with the replacement text after, try one of the following examples:C#You can use the static call when you process on...

  Tags:

  • perl
  • php
  • java
  • javascript
  • vb.net
  • c#
  • regex
  • replace
  • python
  • ruby

  1Vote

  0Comments

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