如何写具有三位有效数字的字符串而不四舍五入

Question

I would like the convert string value with 3 significant digits.

I am using this code :

String s = "0,92";
float f = Float.parseFloat(s);
DecimalFormat formatter = new DecimalFormat("#,###");
String end = formatter.format(f);

The result is end= 0.000. But ı want to get end = 0,920. How can i do that?

Answer 1

This works for me:

String s = "0.92";
float f = Float.parseFloat(s);
DecimalFormat formatter = new DecimalFormat("0.000");
String end = formatter.format(f);
System.out.println(end); 

Please note the '.' in the String s and the pattern in DecimalFormat.
',' here means the 1000 marker, ie. 1,000,000.00 for one million.

Answer 2

If in your current locale the decimal separator is a dot then you will get 0.920. If you want to get the result independent from you current locale to have as decimal separator a comma and as thousand separator a dot you could achieve it for example like this

String s = "0.92";
float f = Float.parseFloat(s);
DecimalFormat formatter = new DecimalFormat("0.000", DecimalFormatSymbols.getInstance(Locale.GERMANY));
String end = formatter.format(f);
System.out.println("end = " + end);

This prints

 end = 0,920