How to get the length of an array in JavaScript
Łukasz Holeczek
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Getting the length of arrays is fundamental for loops, validation, conditional logic, and displaying counts in user interfaces across all JavaScript applications.
With over 25 years of experience in software development and as the creator of CoreUI, I’ve used array length checks extensively in components like pagination controls, progress indicators, and data validation systems where knowing the exact count is crucial.
From my extensive expertise, the built-in length property is the standard and most efficient way to get the number of elements in an array.
This property is automatically maintained by JavaScript and provides instant access to the array size.
How to empty an array in JavaScript
Łukasz Holeczek
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Emptying arrays is essential for resetting application state, clearing user selections, or preparing arrays for new data without breaking existing references in JavaScript applications.
With over 25 years of experience in software development and as the creator of CoreUI, I’ve implemented array clearing in numerous components like shopping carts, form builders, and data tables where arrays need to be reset while maintaining their reference integrity.
From my extensive expertise, the most efficient and reference-preserving solution is setting the array’s length property to 0.
This approach clears all elements while keeping the same array object, ensuring all variables pointing to it remain valid.