Java: Converting a double to a String

问题

I have a double whose value is 10,000,000.00 (ten millions). I have to convert it to a String. When using the method toString I am getting the String "1.0E7" which is correct following the specification. Unfortunately I need the String "10,000,000.00" (or the equivalent depending on the locale).

How can achieve this?

回答1:

Try either

NumberFormat http://java.sun.com/javase/6/docs/api/java/text/NumberFormat.html

DecimalFormat http://java.sun.com/javase/6/docs/api/java/text/DecimalFormat.html

回答2:

In addition to the formatter, you might consider using the java.math.BigDecimal class to represent numbers precisely.

Calculations where complete accuracy is required, such as financial calculations, are best performed with BigDecimal. Floating point math is better for engineering, graphics, and other mathematical computations where some accuracy can be sacrificed for speed.

回答3:

  public static void main(String[] args) throws ParseException {
    double aDouble = 10000000.00;
    DecimalFormat nf = (DecimalFormat) NumberFormat.getInstance(Locale.US);
    String aString = Double.toString(aDouble);
    System.out.println(nf.parse(aString));
  }

回答4:

Look into "DecimalFormat". It lets you format the output pretty much however you want!

来源：https://stackoverflow.com/questions/1521122/java-converting-a-double-to-a-string