function(e){e.preventDefault()if(e.target.classList.contains('item')){originalEl=e.target// 缓存原始图DOM节点cloneEl=originalEl.cloneNode(true)// 克隆图片originalEl.style.opacity=0openPreview()// 打开预览}})functionopenPreview(){// 创建蒙层constmask=document.createElement('div')mask.class...
Array.from(arrayLike[, callback])方法通过在每个数组项上使用callback调用结果来创建一个新数组。 在每个遍历中callback(item[, index[, array]])使用参数调用:当前项、索引和数组本身并且应该返回新项。 如下所示咱们对每个数组元素都递增1: const numbers = [0, 2, 4]; const newNumbers = Array.from(...
[ 1 , 2 , 3 ].some( item => { return item=== 3 }) //true 如果不包含返回false 3.8、类二进制转化 1.终极篇 array .prototype.slice.call( arguments ) //arguments是类数组(伪数组) array .prototype.slice.apply( arguments ) array .from( ar...
r.rawHeadersIn{} 请求头KV Array,只读。请求头Host: localhost Foo: bar foo: bar2输出类似于['Host', 'localhost'], ['Foo', 'bar'], ['foo', 'bar2'] 获取所有的请求头foo可使用r.rawHeadersIn.filter(v=>v[0].toLowerCase() == 'foo').map(v=>v[1]),输出['bar', 'bar2']。
Remove the last element from the array. Show the contents of the array. Iterating through an array - Demo Iterating through the elements of an array, one at a time, is a very common practice in programming. We can use aforloop to iterate over the elements of an array like this: ...
remove useless functions -const f = (...a) => fn(...a); -array.filter((a) => a); +const f = fn; +array.filter(Boolean);remove useless typeof - typeof typeof 'hello'; + typeof 'hello';declare before reference -const {compare} = operator; import {operator} from 'put...
A: Array(4) 0: user_id: (...) username: (...) phone: (...) name: (...) sex: (...) dormitory: (...) status: (...) class_id: (...) create_time: (...) last_login_time: (...) index: 0 1: {…} 2: {…} 3: {…} length: 4 D: Array(8) T: Array(4)...
Notice that all items matching the $elemsMatch clause are returned in the names array. If you require match on ONLY the first item use the MongoDB-compliant $elemMatch operator instead. $aggregate Coverts an array of documents into an array of values that are derived from a key or path ...
Array reduce() Object freeze() Object seal()Changelog#1754 update react plugin readme #1758 Additional Performance enhancements to use provided functions rather than internal polyfill's2.7.3 (Jan 31st, 2022)Updates the @microsoft/applicationinsights-shims module to 2.0.1 Updates React Plugin to v...
… I want to add a Top layer name from current document (or if you have suggestion to enter a text easier by better way) in the middle of these file names. therefore after 3rd character will add the text and after that will be 4th and 5th character. like 1...