JS Tutorial Series 24:javascript-array

1 Arrays-reference types

Built-in objects in JavaScript review arrays using two ways to create arrays array object's property length gets the lengths of the array (number of elements)

2 Common methods:Detecting Arrays

New in instanceof Array.isarray ()//html5

Converting Arrays

ToString ()//Convert the array to a string, each with, split

ValueOf ()//Returns the array object itself join

-Stack operation (advanced post-exit)

-push ()

Pop ()//Remove the last item in the array, modify the Length property

-Queue Operations (FIFO)

-push ()

-shift ()//Remove the first element in the array, modify the Length property

-unshift ()//insert item at the top of the array, return the length of the array

-Sorting Method

Reverse ()//Flip Array

Sort (); Even the array sort is also based on characters, from small to large

How is the sort with parameters implemented?

// join is to link the elements of an array into a string in a special way (the parameter determines what link to use, and the default is a comma link)    var arr = ["AA", "BB", "BB"];     var str1 = arr.join ();     var str2 = Arr.join (""); // If you use a space, there will be a space    between the elements. var str3 = Arr.join (""); // Use empty strings, link elements, seamlessly connect    var str4 = Arr.join ("&");    Console.log (STR1);    Console.log (STR2);    Console.log (STR3);    Console.log (STR4);

3 Other common methods

vararr = ["Guan Yu", "Zhang Fei", "Liu Bei"]; varARR2 = [A]; Console.log (arr);////add element at the end of the array (returns the length of the new array)   //var aaa = Arr.push ("abc");   varAAA = Arr.push ("abc", "Def"); //var aaa = Arr.push (ARR2);   //Console.log (AAA);   //Console.log (arr);//////Deletes an element at the very end of the array (returns the newly deleted element)   //AAA = Arr.pop ();   //Console.log (AAA);   //Console.log (arr);    //Unshift adding elements to the front of the arrayAAA = Arr.unshift ("abc"));    Console.log (AAA);    Console.log (arr); AAA=Arr.shift ();    Console.log (AAA); Console.log (arr);

 varARR1 = ["A", "B", "C"]; varARR2 = [A]; //concat to link the array together    varARR3 =Arr1.concat (ARR2);//Console.log (arr1);//Console.log (ARR2);Console.log (ARR3); //interception of Slice arrays//var arr4 = Arr3.slice (2);//["C", [+]    //var arr4 = Arr3.slice ( -2);//[2,3]   //var arr4 = Arr3.slice (4,2);//[]   //var arr4 = Arr3.slice (2,4);//["C", 1] The index value includes the coordinates that do not include the right side. //Console.log (ARR3);//Console.log (ARR4);////splice manipulating and intercepting the original array//var arr5 = ["1111", "1111", "1111"];//the//replacement element cannot exist as an array, otherwise the entire array is put into the original array.     varARR4 = Arr3.splice (0,3, "1111", "1111", "1111"); Console.log (ARR3);//Console.log (ARR4);

JS Tutorial Series 24:javascript-array