FormDataintermediate

FormData — append() keeps duplicate keys

📖 Usage Example

const fd = new FormData()
fd.append('a', '1')
fd.append('a', '2')
fd.getAll('a')  // → ['1', '2']

getAll() returns an array of all values for a key, including duplicates.

FormData.append() — duplicates

append adds a new entry even if the key already exists, so getAll can return multiple values.

Challenge: Append 'k' twice and verify getAll('k').length is 2.

💡 Hints (1)

• append() never removes existing entries; use set() if you want to replace them

12/15