String formatting in Dart

Question

I was looking up string classes and some other resources, trying to see how to format strings. Primarily, I am trying to Pad out a number to a string, but not precision.

example:

 int a = 0, b = 5, c = 15, d = 46;
 String aout = "", bout = "", cout="", dout="";

 //aout = "00"
 //bout = "05"
 //cout = "15"
 //dout = "46"

When i was looking at int to fixed string precision, it was mostly when dealing with decimals and not prepended padding.

My original thought is that I could do something related to sprintf, such as:

String out = sprintf("%02d", a);

but that didnt seem to work, mostly because It was saying that i am getting a nosuchmethod error. I was not sure if sprintf is in a different package other than core, as i thought this would be related directly to strings.

Answer 1

There's a String.padLeft method you can use:

String out = a.toString().padLeft(2, '0');