如何使用正则表达式从多种URL字符串中提取appName关键词

Got it, let's fix your regex so it works for all four URL cases you listed. Your current pattern /(?<=webapp/)(.*)(?=#)/g relies on a # being present to terminate the match, which is why it fails for examples 1 and 4. Here's a better approach:

The Updated Regex #

/(?<=myapp\/)([^\/#]+)/

How It Works #

• (?<=myapp\/): Positive lookbehind to target the position right after myapp/ (we escape the slash with \/ to avoid regex syntax conflicts)
• ([^\/#]+): Captures one or more characters that are not a slash (/) or hash (#). This ensures we stop matching as soon as we hit either of these characters, or the end of the string—covering all your edge cases.

Testing Against All Examples #

Let’s confirm it works for every URL:

• Example 1: http://localhost:1001/myapp/appName → Matches appName (stops at end of string)
• Example 2: http://localhost:1001/myapp/appName#!/ → Matches appName (stops at #)
• Example 3: http://localhost:1001/myapp/appName#!/Test → Matches appName (stops at #)
• Example 4: http://localhost:1001/myapp/appName/test/what → Matches appName (stops at /)

Usage Example (JavaScript) #

If you’re implementing this in JS, here’s a quick way to extract the value across all your URLs:

const urls = [
  "http://localhost:1001/myapp/appName",
  "http://localhost:1001/myapp/appName#!/",
  "http://localhost:1001/myapp/appName#!/Test",
  "http://localhost:1001/myapp/appName/test/what"
];

const regex = /(?<=myapp\/)([^\/#]+)/;
urls.forEach(url => {
  const appName = url.match(regex)[0];
  console.log(`Extracted appName: ${appName}`);
});

This will log appName for every entry in the list.

内容的提问来源于stack exchange，提问作者Justin Homes