Question

Two quick questions:

1. What would be a RegEx string for three letters and two numbers with space before and after them (i.e. ” LET 12 “)?
2. Would you happen to know any good RegEx resources/tools?

Answer 1

For a good resource, try this website and the program RegexBuddy. You may even be able to figure out the answer to your question yourself using these sites.

To start you off you want something like this:

/^[a-zA-Z]{3}\s+[0-9]{2}$/

But the exact details depend on your requirements. It’s probably a better idea that you learn how to use regular expressions yourself and then write the regular expression instead of just copying the answers here. The small details make a big difference. Examples:

• What is a “letter”? Just A-Z or also foreign letters? What about lower case?
• What is a “number”? Just 0-9 or also foreign numerals? Only integers? Only positive integers? Can there be leading zeros?
• Should there be a single space between the letters and numbers? Or any amount of any whitespace? Even none?
• Do you want to search for this string in a larger text? Or match a line exactly?
• etc..

The answers to these questions will change the regular expression. It would be much faster for you in the long run to learn how to create the regular expression than to completely specify your requirements and wait for other people to reply.

I forgot to mention that there will be a space before and after. How do I include that?

Again you need to consider the questions:

• Do you mean just one space or any amount of spaces? Possibly not always a space but only sometimes?
• Do you mean literally a space character or any whitespace characters?

My guess is:

/^\s+[a-zA-Z]{3}\s+[0-9]{2}\s+$/