retrieve only integer entries from entity

Hi, I have a entity which has member with data type string. Box is the entity and boxnumber is the member, now in boxnumber i can have values like 1,2,box1,4 I want to find maximum of the integer values of boxnumber. I can think of the way is to find only integer values and then find maximum of that.  What is the best way to do that.  can anybody help Thanks
1 answers

You could try a regex to filter out the numbers (or use find or findlast) and do a parse integer on those. Might not work on all values because 4 box 4 might become 44. You could do an export first of all the data to see all combinations and work from there.