The includes() method returns true if an array contains a specified value.The includes() method returns false if the value is not found. The includes() method is case sensitive.Syntaxarray.includes(element, start)ParametersParameter Description element Required.The value to search for. start ...
In the above example, we have used theincludes()method to check whether thelanguagesarray contains elements'C'and'Ruby'. languages.includes("C")returnstruesince the array contains'C'andlanguages.includes("Ruby")returnsfalsesince the array does not contain'Ruby'. Example 2: includes() for Case...
* Array.prototype.[method name] allows you to define/overwrite an objects method * needle is the item you are searching for * this is a special variable that refers to "this" instance of an Array. * returns true if needle is in the array, and false otherwise */Array.prototype.contains=...
javascript的Array没有contains方法,有时候这会不方便,contains方法实现很简单: 代码如下: function contains(a, obj) { var i = a.length; while (i–) { if (a[i] === obj) { return true; } } return false; } 当然我们也可以扩展Array类,如下js 代码如下: Array.prototype.contains = function(ob...
Array 对象的属性 FF: Firefox, N: Netscape, IE: Internet Explorer new Array() new Array(len) new Array([item0,[item1,[item2,...]]] 使用数组对象的方法: var objArray=new Array(); objArray.concact([item1[,item2[,...]]]---将参数列表连接到objArray的后面形成一个新的数组并返回,...
The JavaScript methodtoString()converts an array to a string of (comma separated) array values. Example constfruits = ["Banana","Orange","Apple","Mango"]; document.getElementById("demo").innerHTML= fruits.toString(); Result: Banana,Orange,Apple,Mango ...
var itemExists = Array.contains(array, item); 返回值 如果指定对象是数组中的元素,则为true;否则为false。 备注 使用contains函数确定指定对象是否是Array对象中的元素。 在Mozilla Firefox 中,如果数组中的项已设置为undefined,则调用item 设置为undefined 的contains函数将返回true。同样的情况下,在所有其他浏览器...
这段代码通过prototype定义了数组方法,这样就可以在任意数组调用contains方法 1 2 3 4 5 6 7 8 9 10 11 12 /** * Array.prototype.[method name] allows you to define/overwrite an objects method * needle is the item you are searching for ...
Array operation method For the elements in the array, we have many operation methods, such as:concat()used to connect two arrays.slice()used for slicing,splice()deletes or inserts elements in the middle of the array... contact()
JavaScript Array.concat() Method We can add two or more arrays using this method. This operation doesn’t change the original array, but instead returns a new array that contains the values of the joined arrays. Here is an example to add two array ...