
Introduction
The Regex Tester is an application to use for testing regular expression patterns on a test string, as we create the pattern, rather than testing it on the actual input, which may be sometimes time consuming, especially for large input strings.
Using the RegexTester
The usage is more straight forward. The input string is typed in the test string box, and the pattern is typed in the pattern textbox, as shown above.
Regular Expressions in .NET
Using regular expressions in .NET is pretty simple.. using the regularexpressions namespace available
Imports System.Text.RegularExpressions
dim oRegex as new regex("test pattern")
If oRegex.IsMatch("this is the string to test on") Then
msgbox "Match found"
else
msgbox "Didnt find match"
end if
Points of Interest
The RegexTester with this article has a little nice feature for you to experiment. If the test string box is left empty, the application searches for a file teststring.txt (can be anything if the code attatched is aptly modified), and if the file is found, uses the contents of the file as a test string. This feature comes in needy, when the input string / test string is large.
If you already are conversant with simple .NET programming and the process of creating regular expression patterns, the Regex Tester might be all u need. ;)