regex - Verifying the format of a text file? -

i have application downloads .txt file via ftp, , calls sql insert file data database. want check whether file in correct format before trying insert.

the file should consist of number of rows, each following format:

(4 letter code) (tab) (3 or 4 letter code) (tab) (date dd-mmm-yy) (tab) (variable length text description) (tab) (1 letter code)

is there way check whether every line in file follows pattern, , warn me if doesn't?

sounds typical use case regular expressions. create regex pattern , match against each line in file.

if aren't familiar regex, maybe you'll find this link helpfull in addition links above.

the pattern looking propably this:

    ^\w{4}\t\w{3,4}\t\d{2}\-\d{3}\-\d{2}\t.*\t\w$ 

it match text these (imagine _ tab):

test_foo_12-feb-11_this text_x test_fbar_01-jan-15_bla bka bla_o 

but not:

test123_foo_12-feb-11_this text 

you this:

dim pattern = "^\w{4}\t\w{3,4}\t\d{2}\-\d{3}\-\d{2}\t.*\t\w$" each line in text     console.writeline(string.format("{0} {1}", _                       line, _                       if(regex.ismatch(line, pattern), "is valid", "is invalid")) next