CODEWITHSUNDEEP
javastringformatting
Ryan Conway
Ryan Conway

Reputation: 125

Return String formatted like a credit card number

I have a simple cardNumber String that I'm trying to Format for my System.out.ln

Here is the method that my System.out.ln calls

public String getCardNumber() 
{
    cardNumber = "0000 0000 0000 0000";
    return cardNumber;
}

but the made up part of cardNumber = "0000 0000 0000 0000"; is what I'm trying to format it like, so 12345678912345752 becomes 1234 5678 9124 5752

I've had a look at substring() and stuff but I can't see a simple way to go through every 4 characters and insert a space automatically.

Upvotes: 0

Views: 5281

Answers (3)

user4602302
user4602302

Reputation:

try out the following method:

public String getNumberString() {
    DecimalFormatSymbols symbols = new DecimalFormatSymbols();
    symbols.setGroupingSeparator(' ');
    DecimalFormat fmt = new DecimalFormat("0000,0000,0000,0000", symbols);
    return fmt.format(this.number);
}

Upvotes: 1

James
James

Reputation: 923

To add a space after every 4 characters in a 16 character string, do this.

String number = "1234123412341234";
number = number.substring(0,3) + " " + number.substring(4, 7) + " " + number.substring(8, 11) + " " + number.substring(12, number.length());

Upvotes: 2

Secret
Secret

Reputation: 3358

You just need to manually edit your string

        String input = "1234567891245752";

        StringBuilder result = new StringBuilder();
        for (int i = 0; i < input.length(); i++) {
           if (i % 4 == 0 && i != 0) {
              result.append(" ");
            }

           result.append(input.charAt(i));
        }

        System.out.println(result.toString());

See what we're doing here is iterating over your string, and adding a whitespace in between every 4 characters.

Upvotes: 8

Related Questions