如何使用正则或JS字符串方法从指定URL中提取目标PDF链接？

完全可以实现，以下是两种可直接运行的JavaScript实现方案：

方案1：URI解码+后缀匹配法 #

先对源URL做URI解码还原编码字符，再直接匹配目标PDF路径即可：

const sourceUrl = 'https://s3.ap-south-1.amazonaws.com/abc-test-bucket/test-service/https%3A/%2Fabc-test-bucket.s3.ap-south-1.amazonaws.com/test-Service/0022JUN_29O00190_126072.pdf';
// 解码URL里的转义字符
const decodedStr = decodeURIComponent(sourceUrl);
// 匹配以目标桶域名开头、.pdf结尾的完整路径
const targetPdf = decodedStr.match(/abc-test-bucket\.s3\.ap-south-1\.amazonaws\.com.*\.pdf/)[0];

console.log(targetPdf);
// 输出结果：abc-test-bucket.s3.ap-south-1.amazonaws.com/test-Service/0022JUN_29O00190_126072.pdf

方案2：直接正则提取法 #

不需要提前解码，直接匹配编码后的目标片段再做解码，适合源URL结构固定的场景：

const sourceUrl = 'https://s3.ap-south-1.amazonaws.com/abc-test-bucket/test-service/https%3A/%2Fabc-test-bucket.s3.ap-south-1.amazonaws.com/test-Service/0022JUN_29O00190_126072.pdf';
const matchRule = /%2F(abc-test-bucket\.s3\.ap-south-1\.amazonaws\.com.*?\.pdf)/;
const matchResult = sourceUrl.match(matchRule);
const targetPdf = matchResult ? decodeURIComponent(matchResult[1]) : '';

console.log(targetPdf);
// 输出结果：abc-test-bucket.s3.ap-south-1.amazonaws.com/test-Service/0022JUN_29O00190_126072.pdf

注意：如果后续桶名、区域有变动，只需要调整正则里对应前缀的匹配规则即可正常使用。

内容的提问来源于stack exchange，提问作者Hithesh kumar