(android) decimalformat, uses comma in place of fullstop while formatting with “#.##”

问题

I am developing an Android app where I want to format my double number to #.##, which I have done using below code.

Double BMI = ((fWeight)/(dHeight*dHeight));
DecimalFormat df = new DecimalFormat("0.00");
String sBMI = df.format(BMI);

While testing when the language of hardware is set to English(default language), it works fine, for example if BMI is 2497.227216676656 , it formats sBMI to 2497.23 , but if language is selected to French it formats it to 2497,23. In place of DOT, COMMA is being used which is crashing my app!!!

What is the reason for this?

回答1:

Try this:

Double BMI = ((fWeight)/(dHeight*dHeight));
DecimalFormat df = new DecimalFormat("0.00");
DecimalFormatSymbols dfs = new DecimalFormatSymbols();
dfs.setDecimalSeparator('.');
df.setDecimalFormatSymbols(dfs);
String sBMI = df.format(BMI);

回答2:

You should use the factory static method and not the constructor in order to get the right format.

DecimalFormat df = DecimalFormat.getInstance(Locale.US);

Using US locale will make sure that all formatted data will be in the right form.

来源：https://stackoverflow.com/questions/16557135/android-decimalformat-uses-comma-in-place-of-fullstop-while-formatting-with