Regular Expression Help

Ken Tucker — Mon, 28 Apr 2008 18:31:07 GMT

I got an regualr expression question today from one of my friends. Basically she was using a regular expression to validate a number was 4 or 6 digits long but the expression she was using ^\d{4,6}$ would validate numbers 5 digits long. Lets look at this regular expression ^ means starts with. The \d means number and the {4,6} means 4 to 6 digits long. The $ means ends with. The answer is to use a regular express with an or (the | means or)

Dim regNum As New Regex("^\d{4}$|^\d{6}$")

Debug.Print(regNum.IsMatch("1234").ToString)

Debug.Print(regNum.IsMatch( "12345").ToString)

Debug.Print(regNum.IsMatch("123456").ToString)

Output

True

False

True

regex

Regular Expression Help