Create aSetby applying allfnto all values ofa. Create aSetfromaand all elements inbwhose value, after applyingfndoes not match a value in the previously created set. Return the last set converted to an array. const unionBy = (a, b, fn) => { const s = new Set(a.map(v => fn(...
Array.pop() 方法从数组中删除最后一个元素,并返回该元素的值。此方法更改数组的长度。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 var plants = ["broccoli", "cauliflower", "cabbage", "kale", "tomato"]; console.log(plants.pop()); // expected output: "tomato" console.log(plants); ...
functionrange(start, end, step =1) {returnArray.from({length: (end - start) / step +1},(_, i) =>start + i * step);} 13. 移除重复项 不再需要复杂的过滤操作。让 Set 自行处理。 functionunique(arr) {return[......
console.log(arr.sort(function(a, b){return Math.random()>.5 ? -1 : 1}));// [3, 1, 14, 5, 25] console.log(arr.sort(function(a, b){return Math.random()>.5 ? -1 : 1}));// [5, 1, 3, 14, 25] console.log(arr.sort(function(a, b){return Math.random()>.5 ? -...
varmyArray=['Dashes','are','awesome','!'];console.log(myArray.join('-').split('-')); As you can see, we’re justjoining it with dashesand thensplitting it up again, making itreturn the original array! array.reverse() it reverses an array!Here’s an example: ...
toString :function() {return"Greg"; } };varpeople =[person1, person2]; alert(people);//Nicholas,Gregalert(people.toString());//Nicholas,Gregalert(people.toLocaleString());//Nikolaos,Grigorios 10、数组push和pop方法 varcolors =newArray();//create an arrayvarcount = colors.push("red", "...
2、Array对象属性 Array常见的属性有三个:constructor、length和prototype --->constructor,顾名思义,就是一个构造器,即这个对象是由什么构成的,再通俗一点就是这个对象的类型,见下面例子 var arr = new Array(3); if(arr.constructor==Array) { document.write("This is an Array"); ...
last: element inserted at the end of array. 代码语言:javascript 代码运行次数:0 运行 AI代码解释 functionappend(array,toAppend){constarrayCopy=array.slice();if(toAppend.first){arrayCopy.unshift(toAppend.first);}if(toAppend.last){arrayCopy.push(toAppend.last);}returnarrayCopy;}append([2,3,4...
if (!data) return e.preventDefault() // stops modal from being shown }) 过渡效果 bootstrap-transition.js 关于过渡效果 对于简单的过度效果,只要在引入其它JS文件时一同引入bootstrap-transition.js文件即可。如果你引入的是编译(或压缩)之后的bootstrap.js文件,就不再需要引入此文件了,因为bootstrap.js文件...
Array.from() Array.from() is a static property of the JavaScript Array object. You can only use it as Array.from(). Using x.from(), where x is an array will return undefined. Syntax Array.from(object, mapFunction, thisValue)