CODEWITHSUNDEEP
javaandroidregex
user3211607
user3211607

Reputation: 35

Checking the number of digits from a string

Does the following code ensure that the 'myteststring' contains only two digit numbers?If not, how to modify it?

if(myteststring.matches("^[0-9]*\\$")) 
{
// Do something
}
else {
// Do something else
}

Upvotes: 0

Views: 74

Answers (2)

Cory
Cory

Reputation: 325

To match a string that contains at least one pair of digits, any combination of characters, and with the restriction that numbers are exactly two digits:

myteststring.matches("^[^0-9]*([0-9]{2}[^0-9]+)*[0-9]{2}[^0-9]*$")

To include the empty string:

myteststring.matches("^[^0-9]*([0-9]{2}[^0-9]+)*([0-9]{2})?[^0-9]*$")

To match a sting that contains exactly two digits:

myteststring.matches("^[0-9]{2}$")

Or

myteststring.matches("^[0-9][0-9]$")

The ^ means match the beginning of the line. When used inside of the square brackets, it matches the opposite of the pattern.

The [0-9] means match one of the. numbers from 0 through 9.

The {2} means match the previous regex twice.

The $ means match the end of line.

Upvotes: 2

TheLostMind
TheLostMind

Reputation: 36304

use (\\d{2})+ . This checks for pairs of digits. demo here

Output : 

myString ="123" --  > false
myString ="12" -- > true
myString ="1234" --> true

Upvotes: 2

Related Questions