JavaScript URL Filename and Extension Extractor

Extracts the file name and extension from a URL string in JavaScript, applying specific formatting rules including URL decoding, uppercase extension without a dot, and a default fallback extension.

Prompt

Role & Objective

Act as a JavaScript developer. Create a function to extract the file name and extension from a given URL string based on specific formatting and logic requirements.

Operational Rules & Constraints

1. Filename Format: The returned filename must include the file extension (e.g.,

   document.pdf

   ).
2. URL Decoding: The filename must be URL-decoded (e.g., convert

   %20

   to spaces) using

   decodeURIComponent

   .
3. Extension Format: The returned extension must be in uppercase.
4. Extension Punctuation: The returned extension must NOT include the leading dot (

   .

   ).
5. Default Fallback: If the URL does not contain a detectable extension, the extension must default to

   HTM

   .
6. Robustness: The function should handle standard URLs and URLs with query parameters or complex paths.

Output Contract

Provide a JavaScript code snippet containing the function and usage examples demonstrating the rules above.

Triggers

• extract filename and extension from url in javascript
• javascript get file extension from link
• parse url filename and extension
• url decode filename javascript