c# - 用于捕获括号中数字的正则表达式

Question

示例

Alarm Level 1 (D1) [Low (15.7)]
Alarm Level 2 [High (-12.7)]

我想从警报级别1获得15.7，从警报级别2获得-12.7。我尝试使用 \((.*?)\) 但它在警报级别 1 中同时获得 D1 和 15.7。

Answer 1

在这里，我们可以尝试使用简单的捕获组来收集数字:

\(([0-9-.]+)\)

测试

using System;
using System.Text.RegularExpressions;

public class Example
{
    public static void Main()
    {
        string pattern = @"\(([0-9\-\.]+)\)";
        string input = @"Alarm Level 1 (D1) [Low (15.7)]
Alarm Level 2 [High (-12.7)]";
        RegexOptions options = RegexOptions.Multiline;

        foreach (Match m in Regex.Matches(input, pattern, options))
        {
            Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
        }
    }
}

const regex = /\(([0-9-.]+)\)/gm;
const str = `Alarm Level 1 (D1) [Low (15.7)]
Alarm Level 2 [High (-12.7)]`;
let m;

while ((m = regex.exec(str)) !== null) {
    // This is necessary to avoid infinite loops with zero-width matches
    if (m.index === regex.lastIndex) {
        regex.lastIndex++;
    }
    
    // The result can be accessed through the `m`-variable.
    m.forEach((match, groupIndex) => {
        console.log(`Found match, group ${groupIndex}: ${match}`);
    });
}

DEMO

正则表达式电路

jex.im可视化正则表达式: