如何在int中添加逗号？

Question

我有以下代码，

Scanner cin = new Scanner(System.in);

System.out.print("Part-1- Enter the amount inout ($ 1,567.00):");
String amountStr = cin.nextLine();

String amountStr2 = amountStr.replace("$" , "");
String amountStr3 = amountStr2.replace("," , "");
double amountDouble = Double.parseDouble(amountStr3);

double quarters = (amountDouble / .25);
double quarters2 = Math.floor(quarters);

int quartersFinal = (int) quarters2;

我想结果返回数字结果6,269。现在，代码返回6269.我如何添加逗号？

Answer 1

您可以使用DecimalFormat

Scanner cin = new Scanner(System.in);
System.out.print("Part-1- Enter the amount inout ($ 1,567.00):");
String amountStr = cin.nextLine();
String amountStr2 = amountStr.replace("$" , "");
String amountStr3 = amountStr2.replace("," , "");
double amountDouble = Double.parseDouble(amountStr3);
double quarters = (amountDouble / .25);
double quarters2 = Math.floor(quarters);
DecimalFormat df = new DecimalFormat("#,###");
System.out.println(df.format(quarters2));

Out put：

6,268

Answer 2

试试这个

DecimalFormat df = new DecimalFormat("#,###.##");
String amountStr2 = amountStr.replace("$" , "");
String amountStr3 = amountStr2.replace("," , "");
double amountDouble = Double.parseDouble(amountStr3);
df.format(amountDouble);

Answer 3

详细阅读string.Format（...）的文档。你将来需要多次。