I am still learning to do regex, but this one gets me stumped for a while. I am trying to make a regex expression to match the strings like TOL1234567 or tol1234567. There should be ‘TOL’ at the first and then there will be 7 numbers after. No special characters are needed.

^(?=(?:[tolTOL])(((?=(?:[^0-9rn]*[0-9]){7}))$ – it doesn’t work well. 🙁

I appreciate any help. Thank you!