toCollection().toArray() 这个组合方法首先通过 toCollection() 创建一个实时集合,然后立即调用 toArray() 方法来执行查询并返回一个 Promise,该 Promise 解析为包含所有当前匹配结果的数组。 虽然这看起来和直接使用 toArray() 类似,但主要区别在于,如果 toCollection() 创建的集
function(outer, collection) { return{ outer: outer, collection: collection.toArray() } }) .toArray(); result: [{ outer: 3, collection: [] }, { outer: 3, collection: [] }, { outer: 4, collection: [4] }, { outer: 5, collection: [5] }, { outer: 6, collection: [6, 6]...
Javascript Array toArray() /*//www.java2s.com* Takes an array-like collection as parameter, returning its proper "arrayified" equivalent. */Array.toArray =function(pseudoArray) {if(!pseudoArray) {return[]; } else {varresult = [];for(vari=0; i < pseudoArray.length; i++) { result...
To accomplish this, use a wrapping element. Programmatic API We also believe you should be able to use all Bootstrap plugins purely through the JavaScript API. All public APIs are single, chainable methods, and return the collection acted upon. $('.btn.danger').button('toggle').addClass('...
("click",showNextImage);prevBtn.addEventListener("click",showPrevImage);//document.getElementsByClassName返回HTML collection,所以我们使用 "Array.from" 方法来获取一个可迭代的对象constimages=Array.from(document.getElementsByClassName("carousel__img"));consttotalImages=images.length;letcurrentImageIndex=0;...
array1,...Required. The array(s) to be concatenated. Return Value TypeDescription ArrayThe content from the joined arrays. More Examples Concatenate strings and numbers: constarr1 = ["Cecilie","Lone"]; constarr2 = [1,2,3]; constarr3 = arr1.concat(arr2); ...
An HTMLCollection object is an array-like list (collection) of HTML elements.The following code selects all elements in a document:Example const myCollection = document.getElementsByTagName("p"); The elements in the collection can be accessed by an index number. To access the second eleme...
引用计数垃圾收集 Reference-counting garbage collection 这是最初级的垃圾收集算法。此算法把“对象是否不再需要”简化定义为“对象有没有其他对象引用到它”。如果没有引用指向该对象(零引用),对象将被垃圾回收机制回收。 下述例子,使用了MDN中的例子,而并没有用原文中,因为发现了作者这部分内容完全来自 MDN o(╥...
Convert array to collection(object) in JS The best way to convert array to object in JavaScript ['a','b','c'] to { '0':'a', '1':'b', '2':'c' } 1. JavaScript Example 1 – Convert array to object const namesArr =["Rajat","Proto","Coders"]; ...
MongoClient.Db.Collection.countDocuments JavaScript // get list of databasesconstlistResult =awaitclient.db().admin().listDatabases();console.log("Databases:\n");// loop through databasesforawait(letdatabaseoflistResult.databases) {console.log(`\t${database.name}\n`);// get database client...