A Short Notes of array methods:

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• A Short Notes of array methods:
  • To add/remove elements:
  • To search among elements:
  • To iterate over elements:
  • To transform the array:
  • Additionally:

To add/remove elements:

• push(...items) – adds items to the end,
• pop() – extracts an item from the end,
• shift() – extracts an item from the beginning,
• unshift(...items) – adds items to the beginning.
• splice(pos, deleteCount, ...items) – at index position deletes the deleteCount elements and inserts items.
• slice(start, end) – creates a new array, copies elements from index start till end (not inclusive) into it.
• concat(...items)– returns a new array: copies all members of the current one and adds items to it. If any of items is an array, then its elements are taken.

To search among elements:

• indexOf/lastIndexOf(item, pos) – look for item starting from position pos, and return the index or -1 if not found.
• includes(value) – returns true if the array has value, otherwise false.
• find/filter(func) – filter elements through the function, return first/all values that make it return true.
• findIndex is like find, but returns the index instead of a value.

To iterate over elements:

• forEach(func) – calls func for every element, does not return anything.

To transform the array:

• map(func) – creates a new array from results of calling func for every element.
• sort(func) – sorts the array in-place, then returns it.
• reverse() – reverses the array in-place, then returns it.
• split/join – convert a string to array and back.
• reduce/reduceRight(func, initial) – calculate a single value over the array by calling func for each element and passing an intermediate result between the calls.

Additionally:

• Array.isArray(value) checks value for being an array, if so returns true, otherwise false.