Regular expression for a hexadecimal number?

Question

How do I create a regular expression that detects hexadecimal numbers in a text?

For example, ‘0x0f4’, ‘0acdadecf822eeff32aca5830e438cb54aa722e3’, and ‘8BADF00D’.

Answer 1

It's worth mentioning that detecting an MD5 (which is one of the examples) can be done with:

[0-9a-fA-F]{32}