How do you decode or encode a URL in JavaScript?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of JavaScript conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
encodeURI() function is used to encode an URL. This function requires a URL string as a parameter and return that encoded string.decodeURI() function is used to decode an URL. This function requires an encoded URL string as parameter and return that decoded string.
Note: If you want to encode characters such as / ? : @ & = + $ # then you need to use encodeURIComponent().
let uri = "employeeDetails?name=john&occupation=manager";
let encoded_uri = encodeURI(uri);
let decoded_uri = decodeURI(encoded_uri);
Candidate Response Strategy & Interview Tips
- Start with a concise one-sentence summary: Deliver a direct, confident answer first before expanding into nuances.
- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
- Prepare for interviewer follow-ups: Technical hiring panels frequently probe deeper into concurrency, backward compatibility, or alternative libraries.