Summary of JS array method

Summary of common methods for arrays

  does not change the original array 1, array.length;                      //Get array length 2, array.join ();                        //The array is stitched together with the string passed in, returning the stitched string, with the default "," to splice. 3, Array.concat ();                    //can add multiple elements passed in to the end of the array, or Arrays 4, Array.slice ()   &NBSP ;                    //for copying part of the array below, the incoming two parameters specify the start and end positions respectively, and negative numbers are reversed. 5, array.tostring ()                  //equivalent to Array.join (', '); 6, Array.every ( function (Value,index,array)) {});    //For each element in the array for conditional detection, all satisfied returns True, otherwise false;7, array.some (function (Value,index,array)) {}) are returned;    //is used for conditional detection of each element in an array, returns true if one satisfies, otherwise returns FALSE;8, Array.filter (function (Value,index,array)) {});    //For filtering the array elements that satisfy the condition and returning them to the new array; 9, Array.map (function (Value,index,array)) {});    //To modify each element in an array and return a new array of its constituent 10, ARRAy.foreach (function (Value,index,array)) {});              //for each element operation in an array, no return value 11, array.reduce (function (Prev,cur,index,array) { }, [init]),  //all items of the iterated algebraic group, and then constructs a final returned value. The first parameter is the handler function, and the arguments are the previous value, the current value, the index, and the array.  //The Second optional parameter is the initial value, and if omitted, the first element of the array is  //in an empty array, and there is no initial value, which results in an error; the  //array has only one value and no initial value, or an empty array but has an initial value, it returns that value.  //Example:  var values = [1,2,3,4,5]; var sum = values.reduce (function (prev, cur, index, values) {        return prev + cur; });  12, Array.reduceright (function (Prev,cur,index,array) {}, [init]);  Works the same as the reduce method, but starts at the right end.  13, Array.indexof (Index,[start]);        //To find the specified array element from the start position (optional), return its index position, and return 114, Array.lastindexof (Index,[start]) if not found;    //similar to the IndexOf method, but it is looked up from the right end.   Change the original array 1, Array.reverse ();      //reverse the elements in an array, returning an array of 2, Array.Sort () in reverse order;          //arrange array elements, default an alphabetical list, and uppercase letters in front of lowercase letters, return the array   Expand: Arrange the numbers  array.sort ( function (A, b) {&NBsp                                 return a- b;                           });  case insensitive: Arra Y.sort (function (A, b) {                            & nbsp      var m = a.tolowercase (),                      nbsp                   n = b.tolowercase ();          &NBS P                        if (M > N) {      &NBS P                                  retu RN 1                                   Else {                              &N Bsp          return-1;                      & nbsp            }                      &N Bsp    });  3, Array.splice ()          //used to insert or delete elements in an array, the first parameter specifies the position of the element to be deleted, The second parameter specifies the number of deleted elements,                              &N Bsp      //If you remove all subsequent elements, the third and subsequent elements are added to the array at the specified position. This function returns                                 &NBS P    //An array of deleted elements, and returns an empty array if no elements are removed.  4, Array.push ()        //adds one or more elements to the end of the array, and returns the length of the array. 5, Array.pop ()        //delete an element at the end of the array, returning the deleted element 6, Array.unshift()    //Add one or more elements to the head of the array and return the array length. 7, Array.shift ()      //delete an element of the array header, returning the deleted element

JS Array Method Summary