Question

我正在学习regexp.my regexp是：

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我的示例数据是：/^([0-5][0-9]|60):/g

一切都很好。现在我想在之前提取第一个：。即：60但是当我尝试使用1美元时。它返回60:40:60 Lua。任何的想法？

Answer 1

那个怎么样：

^(?:[0-5][0-9]|60)(?=:)

Demo

或者按照您的验证方式，您可以尝试：

^(?:[0-5][0-9]|60)(?=:\d{2}:\d{2}.*)

说明：

^(?:[0-5][0-9]|60) - 与您的相同
(?=:\d{2}:\d{2}.*) - 积极前瞻以确保前一个模式后面跟着2位冒号2 digt，然后是其余的零或更长的字符串。

Demo 2

由于它似乎没有根据您的需要提供服务，因此有一个解决方案可以捕获3组，其中组1以您想要的数字开头：

const regex = /^([0-5][0-9]|60):([0-5][0-9]|60):([0-5][0-9]|60).*$/gm;
const str = `60:40:60 Lua`;
let m;

if ((m = regex.exec(str)) !== null) {
console.log(m[1]);
console.log(m[2]);
console.log(m[3]);
}

如何使用regexp捕获第一次出现的预定义输入？

1 个答案: