Understanding printf()

[chris_zeman]

I've messed around with PHP a little over the past few years, but never really stuck with it and now I'm determined to. I'm starting from scratch, and I do mean scratch.

I'm having a problem understanding printf(). I'm sure it's easy and once someone points it out to me I'm gonna hit my head on the wall. 🙂

The example I'm looking at is:

printf("$%01.2f", 43.2); //$43.20

My problem is that I don't understand how the arguments work.

Any help would be greatly appreciated! 🙂

Thank you,
Chris

[planetsim]

Im not sure with the PHP of it however this is more of a c function which works exactly the same in PHP.

printf is just formated output. Basically you can have normal test and formatted text

[man]sprintf[/man] Manual page has information on the %f etc

however you have the following more common used

%s = String
%d = Decimal
%f = Float

Now you can add things to these formatted values there are more on the manual page but they are the more commonly used.

You can add number to it so e.g.

printf("%20d",100);

Would add a pad of 20 blank characters and starting from the right put the 100 on so it looks something like this

                 20

If you did it different like

printf("%20.2f",100);

You have made 100 a float and padded by 20 with 2 decimals required rounded up if necessary. so the output would be

              100.00

You may need to view source to see it correctly.

I hope this helps

[chris_zeman]

OK, I get it now. Now I understand what I wasn't seeing before.

Thank you for taking the time to explain it to me. Have a great holiday!

Chris