
Fermin Perdomo
Full Stack Developer
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How unique an array of object with js by properties
Unique by a Single PropertyIf you want the objects in the array to be unique based on one property (e.g., id):Unique by Multiple PropertiesIf you want uniqueness based on a combination of properties, you can create a unique key by combining the values of those properties:Using
filter
for SimplicityAlternatively, you can use the filter
method for uniqueness by checking if an item's index matches its first occurrence:ExplanationMap and Set: Efficient for large arrays because they use hashing for uniqueness.
filter + findIndex: More readable but can be slower for large arrays due to nested iterations.
Custom Combination Key: Use when uniqueness depends on multiple properties.