When not to use Regex in C# (or Java, C++, etc.)

Question

It is clear that there are lots of problems that look like a simple regex expression will solve, but which prove to be very hard to solve with regex.

<

Answer 1

Use regular expressions for recognizing (regular) patterns in text. Don't use it for parsing text into data structures. Don't use regular expressions when the expression becomes very large.

Often it's not clear when not to use a regular expression. For example, you shouldn't use regular expressions for proper email address verification. At first it may seem easy, but the specification for valid email addresses isn't as regular as you might think. You could use a regular expression to initial searching of email address candidates. But you need a parser to actually verify if the address candidate conforms to the given standard.