检查String是否包含数字Java [英] Check if a String contains numbers Java

问题描述

我正在编写一个程序，用户按以下格式输入字符串：

I'm writing a program where the user enters a String in the following format:

"What is the square of 10?"

1. 我需要检查字符串中是否有数字


2. 然后只提取数字。


3. 如果我使用 .contains（\\\\ +）或 .contains（[ 0-9] +），无论输入是什么，程序都无法在String中找到数字，但 .matches（\\d + ）仅在只有数字时才有效。

1. I need to check that there is a number in the String
2. and then extract just the number.
3. If i use .contains("\\d+") or .contains("[0-9]+"), the program can't find a number in the String, no matter what the input is, but .matches("\\d+")will only work when there is only numbers.

我可以使用什么作为查找解决方案和提取？

What can I use as a solution for finding and extracting?

推荐答案

我选择的解决方案如下：

The solution I went with looks like this:

Pattern numberPat = Pattern.compile("\\d+");
Matcher matcher1 = numberPat.matcher(line);

Pattern stringPat = Pattern.compile("What is the square of", Pattern.CASE_INSENSITIVE);
Matcher matcher2 = stringPat.matcher(line);

if (matcher1.find() && matcher2.find())
{
    int number = Integer.parseInt(matcher1.group());                    
    pw.println(number + " squared = " + (number * number));
}

我确定这不是一个完美的解决方案，但它符合我的需求。谢谢大家的帮助。 ：）

I'm sure it's not a perfect solution, but it suited my needs. Thank you all for the help. :)

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