function isEmpty(obj) { for(var prop in obj) { if(obj.hasOwnProperty(prop)) return false; } return true; } In the above code, we will loop through object properties and if an object has at least one property, then it will enter the loop and return false. If the object doesn’t...
letvalue;value// 👈 null and undefined check&&Object.keys(value).length===0&&value.constructor===Object;value=null;// nullvalue=undefined;// undefined Perfect, no error is thrown 😁 #B. Empty Object Check in Older Browsers What if you need to support older browsers? Heck, who am I...
Javascript中如何判断对象是否为空 发现了一个巧妙的实现: 需要检查一个对象(Object)是否为空,即不包含任何元素。Javascript 中的对象就是一个字典,其中包含了一系列的键值对(Key Value Pair)。检查一个对象是否为空,等价于检查对象中有没有键值对。写成代码,形如: if (isEmptyObject(obj)) { // obj is emp...
Javascript 中的对象就是一个字典,其中包含了一系列的键值对(Key Value Pair)。检查一个对象是否为空,等价于检查对象中有没有键值对。写成代码,形如: if(isEmptyObject(obj)){ // obj is empty }else{ // not empty } 至于isEmptyObject 的实现,jQuery 中有一个很有想法的方式,请看代码: functionisEmpty...
console.log(isEmptyObject(notEmptyObject)); //returns false Here, we created two JavaScript objects. The first object is empty, and the second one is not empty. If you pass them into our custom JavaScript function, you will see that it returns TRUE for the first one and FALSE for the ...
现在,您可以使用此方法通过 if 语句检查对象是否为空,或创建一个进行检查的函数。 const isObjectEmpty = (objectName) => { return Object.keys(objectName).length === 0 } 这将返回true或false。如果对象为空,则返回true,否则返回false。 let userDetails = { ...
Read this tutorial and find methods of checking whether a JavaScript object is empty or not. Choose the best one for you and get the code immediately.
JavaScript ES6使用Object.getOwnPropertyNames()方法检查空对象 Object.getOwnPropertyNames() 方法返回所有属性或键名称的数组。此方法还返回给定对象的不可枚举属性。 例子如下: constemptyObject={};if(Object.getOwnPropertyNames(emptyObject).length===0){console.log("The object is empty");}// Output: "The obj...
The Object.keys() method returns an array of enumerable property names of a given object. And thus, we can use it to check if an object has any properties by counting the length of this array. Let’s have a look at the following example. 1 function isEmptyObject(obj) { 2 return ...
$.isEmptyObject 我们知道是判断对象是否为空,如果不存在也返回false,但是我想问的是:这个和我们直接写判断有什么区别呢:比如