Question

我有一个字符串，我想提取其中的浮点数。我已经使用matcher.group（）函数成功完成了此操作，但我只想单独显示它们。这是我的代码

String regex="([0-9]+[.][0-9]+)";
String input= "You have bought USD 1.00 Whatsapp for 784024487. Your new wallet balance is USD 1.04. Happy Birthday EcoCash for turning 7years. Live Life the EcoCash Way.";

Pattern pattern=Pattern.compile(regex);
Matcher matcher=pattern.matcher(input);

while(matcher.find())
  {
System.out.println("First float is "+matcher.group());
  }
}

我得到的答案是：第一浮动为1.00 第一浮动为1.04

但是我想说：第一浮动为1.00 第二浮动为1.04

我该怎么做？

Answer 1

类似的东西？

int k = 1;
while(matcher.find())
{
   System.out.println("Float " + k + " is "+matcher.group());
   k++;
}

这将输出如下内容：浮点数1为1.00浮点数2为1.04

Answer 2

使用以下方法将数字转换为序数形式，然后使用它来显示

public static String ordinal(int i) {
        String[] sufixes = new String[]{"th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th"};
        switch (i % 100) {
            case 11:
            case 12:
            case 13:
                return i + "th";
            default:
                return i + sufixes[i % 10];

        }
 }

public static void main(String[] args) {
        String regex = "([0-9]+[.][0-9]+)";
        String input = "You have bought USD 1.00 Whatsapp for 784024487. Your new wallet balance is USD 1.04. Happy Birthday EcoCash for turning 7years. Live Life the EcoCash Way.";
        Pattern pattern = Pattern.compile(regex);
        Matcher matcher = pattern.matcher(input);
        int number = 1;
        while (matcher.find()) {
            System.out.println(ordinal(number++) + " float is " + matcher.group());
        }
}

Answer 3

您需要在循环内有一个计数器，并根据计数器写输出正确的字。而是从显示诸如“ Float #n is：xxx”之类的东西而不是单词开始。

Answer 4

您可以编写一个返回后缀的方法，例如st，nd，rd，并在代码中使用它，例如：

private static String getPostFix(int number) {
    if(number % 10 == 1) {
        return "st";
    } else if(number % 2 == 0) {
        return "nd";
    } else if(number % 3 == 0) {
        return "rd";
    } else {
        return "th";
    }
}

代码为：

String regex="([0-9]+[.][0-9]+)";
String input= "You have bought USD 1.00 Whatsapp for 784024487. Your new wallet balance is USD 1.04. Happy Birthday EcoCash for turning 7years. Live Life the EcoCash Way.";

Pattern pattern=Pattern.compile(regex);
Matcher matcher=pattern.matcher(input);

int i=0;
while(matcher.find()){
    System.out.println((++i) + getPostFix(i) + " Float is :" + matcher.group());
}

Java如何从字符串中提取浮点数并单独显示

4 个答案: