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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 ...
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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...
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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 ...
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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...
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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)://....
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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...
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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 ...
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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...
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- php
- perl
- javascript
- java
- vb.net
- c#
- objects
- regex
- python
- ruby
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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...
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- python
- perl
- javascript
- java
- vb.net
- c#
- search
- regex
- php
- ruby
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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 expression before with the replacement text after, try one of the following examples:C#You can use the static call when you process on...
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- perl
- php
- java
- javascript
- vb.net
- c#
- regex
- replace
- python
- ruby
2Votes

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