Remove the leading 0's till the decimal

问题

I want to remove the leading zeros in the decimal numbers.

So i want the output should be .324 not 0.324. I tried str.replaceFirst("^0+(?!$)", ""); Didn't work and i also tried the regex! No results! And yes I am working with BigDecimal.

回答1:

Try this

str = str.replaceFirst("^0\\.", ".");

回答2:

if you are trying to format BigDecimal having value 0.324 to .324. Then below works

    BigDecimal bd=new BigDecimal("0.23");// this will replace with your BigDecimal
    DecimalFormat df=null;
    //check if number is a fraction
    if(bd.remainder(BigDecimal.TEN).compareTo(BigDecimal.ZERO)>0)
      df=new DecimalFormat(".###");
    else
      df=new DecimalFormat("##");

    System.out.print(df.format(bd));// .format returns string as .23

0.23->.23
0->0
90->90
80.12->80.12

回答3:

do you want this for printing purposes? you wont be able to do any math using this, so i guess yes. then you could do:

BigDecimal number =new BigDecimal(0.254); 
       System.out.println(number.toString().substring(number.toString().indexOf("0.")+1));

output

.254000000000000003552713678800500929355621337890625

来源：https://stackoverflow.com/questions/30959109/remove-the-leading-0s-till-the-decimal