![]() You can use the same technique to slice the array starting from the end of it. The slice method copies up to, but not including, the element indicated. It works well when the array is empty: var array = Ĭonsole.log(array.slice( -1)) // return Ĭonsole.log(array.slice( -1)) // returns undefined The slice method returns an Array object containing the specified portion of arrayObj. The syntax1 is a lot simpler to write and read and I will certainly start using it when performance is not a concern: Empty array Slicing the array is 20 times more taxing than accessing the last item directly. In javascript, there is a method known as the slice () method for selecting part of the given elements and return this as a new array object without changing the original array. I created the following quick performance test in Node (v5.6.0) to see how this syntax ( syntax1.js) compares to the more traditional one ( syntax2.js): index.js console.time( 'array slice') It is a very neat and readable alternative to the often seen: syntax2.js var array = O método slice () retorna uma cópia de parte de um array a partir de um subarray criado entre as posições início e fim (fim não é incluído) de um array original. ![]() ![]() Tip 7 in this Useful JavaScript Hacks Article proposes the following method to get the last item in an array. After splitting the string into multiple substrings, the split () method puts them in an array and returns it. The splice () method is a mutating method. How does slice return a copy of the original. A new array containing the extracted elements. If end is greater than the length of the sequence, slice extracts through to the end of the sequence ( arr. The splitter can be a single character, another string, or a regular expression. How does slice extract from an array in JavaScript If end is omitted, slice extracts through the end of the sequence ( arr. ![]() If not specified, splice () will only remove elements from the array. The split () Method in JavaScript The split () method splits (divides) a string into two or more substrings depending on a splitter (or divider). ![]() , itemN (optional) - The elements to add to the start index. deleteCount (optional) - The number of items to remove from start. This article discusses the preferred way to retrieve the last element of an Array in JavaScript. The splice () method takes in: start - The index from where the array is changed. ![]()
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