Using Regular Expressions in ASP.NET

From Dan Mabbutt, former About.com Guide

Here's how the regex matches our example string starting at the left side of both.

1. < matches <
   
2. /? matches 0 or 1 occurances of / (there are zero in our string)
   
3. .+ matches 1 or more occurances of any character ("H1" in our string)
   
4. /? matches 0 or 1 occurances of / (again, there are zero in our string)
   
5. > matches >
   
6. .+ matches 1 or more occurances of any character ("About Visual Basic!" in our string)
   
7. < matches <
   
8. /? matches 0 or 1 occurances of / (now there is 1 in our string)
   
9. .+ matches 1 or more occurances of any character ("H1" again)
   
10. /? matches 0 or 1 occurances of / (zero again)
    
11. > matches >

• The Intersection of Regular Expressions and ASP.NET
• Creating a URL Validation ASP.NET Application
• Creating Your Own RegEx
• How a RegEx Works
• Step by Step - Matching Against the RegEx
• Lessons Learned from our HTML Validation RegEx
• Client Side RegEx Validation