The problem is that Array is actually under the umbrella ofObjectsdata type. Sotypeofis indeed returning truthfully. Unfortunately, that isn't really helpful for us who just want to check if the value is an arra
functionmyFunction(){varfruits=["Banana","Orange","Apple","Mango"];varx=document.getElementById("demo");x.innerHTML=Array.isArray(fruits);} 尝试一下 » 定义和用法 isArray() 方法用于判断一个对象是否为数组。 如果对象是数组返回 true,否则返回 false。
This is the fastest method on Chrome, and most likely all other browsers. All arrays are objects, so checking the constructor property is a fast process for JavaScript engines. If you are having issues with finding out if an objects property is an array, you must first check if the propert...
Vue Js Check if a Variable is an Array: In Vue.js, you can use the Array.isArray() method to check if a variable is an array or not. This method takes one parameter, which is the variable you want to check, and returns a boolean value. If the variabl
Example: Check Array Using Array.isArray() // program to check if an object is an arrayfunctioncheckObject(arr){// check if arr is arrayconstresult =Array.isArray(arr);if(result) {console.log(`[${arr}] is an array.`); }else{console.log(`${arr}is not an array.`); ...
var valueToCheck = 'banana'; if (myArray.includes(valueToCheck)) { console.log('数组包含该值。'); } else { console.log('数组不包含该值。'); } 在这个例子中,数组myArray包含了多个水果名称的字符串。我们想检测字符串'banana'是否为其成员。通过includes()可以很容易地实现检测。
https://www.codesolutionstuff.com/javascript-program-to-check-if-an-object-is-an-array/ Object.prototype 中的函数 toString 方法是确定对象是否是给定类的实例的最佳方法。 var数组列表 = [1,2,3]; 当我们在 JavaScript 中使用方法重载时,类型检查对象是最伟大的应用之一。假设我们有一个名为 greet 的方...
虽然Array也继承自Object,但js在Array.prototype上重写了toString,而我们通过Object.prototype.toString.call(arr)实际上是通过原型链调用了。 var toString = Object.prototype.toString; toString.call(new Date); // [object Date] 判断其他对象类型 toString.call(new String); // [object String] ...
var b = false; var list = [{test:'test'}]; var n = null; function func(){} 通过测试,使用如:str == String.constructor的形式,只能判断Object、Array、String、Boolean、Number,对于null、function、undefind这些会报异常。 参考: http://stackoverflow.com/questions/4775722/check-if-object-is-arra...
Discover how to efficiently check if a value exists in an array using JavaScript. Learn essential techniques for seamless array manipulation.