// expected output: Array ["camel", "duck", "elephant"] console.log(animals.slice(2, 4)); // expected output: Array ["camel", "duck"] 8.shift shift()是一个内置的JavaScript函数,用于从数组中删除第一个元素。shift()函数直接修改您正在使用的JavaScript数组。shift()返回从数组中移除的项。 ...
slice() //begin和end的默认值是0和结尾 concat:合并数组 代码语言:javascript 复制 const array3 = array1.concat(array2); find/findIndex:查找符合条件的元素 代码语言:javascript 复制 const found = array1.find(element => element > 10); //findIndex返回索引 const isLargeNumberIndex = array1.find...
sliceLength( slice ) Returns the number of elements in anormalized slice. varSlice=require('@stdlib/slice-ctor');varnormalizeSlice=require('@stdlib/slice-base-normalize-slice');vars=normalizeSlice(newSlice(-3,null,-1),10,false);// returns <Slice>varlen=sliceLength(s);// returns 8 ...
const array1 = [1, 2, 3]; const firstElement = array1.shift(); console.log(array1); // expected output: Array [2, 3] console.log(firstElement); // expected output: 1 3.slice(): 该方法同concat()一样是返回一个新数组,不会影响原数组,只不过slice()是用来裁剪数组的,返回裁剪下来的...
9. 10. function logArrayElements(element, index, array) { console.log('a[' + index + '] = ' + element); } // Notice that index 2 is skipped since there is no item at // that position in the array. [2, 5, , 9].forEach(logArrayElements); // logs: // a[0] = 2 //...
slice(startIndex[, endIndex]):从原始数组中提取指定范围的元素,返回一个新的数组。startIndex是起始索引,endIndex是可选参数,表示结束索引(不包含在提取的结果中)。 letarr=['apple','banana','orange','grape'];letslicedArray=arr.slice(1,3);console.log(slicedArray);// 输出 ['banana', 'orange']...
The content can be an HTML string, a DOM node or an array of nodes. $('ul').prepend('first list item')prependTo prependTo(target) ⇒ self Prepend elements of the current collection inside each of the target elements. This is like prepend, only with reversed operands. $('first li...
2、join()[Array.prototype.join]=>MDN join()方法将一个数组(或一个类数组对象)的所有元素连接成一个字符串并返回这个字符串。 varelements = ['Fire', 'Wind', 'Rain']; console.log(elements.join());//expected output: Fire,Wind,Rainconsole.log(elements.join(''));//expected output: FireWindR...
A JSVolume is a 3d of grid elements represented internally by a single-dimensional array. This provides superior performance to a multi-dimensional array, which isn't a real thing in javascript anyway (if you want multidimensional arrays of arbitrary dimensions, try an NDArray library)....
简单的说 Node.js 就是运行在服务端的 JavaScript。 Node.js 是一个基于 Chrome JavaScript 运行时建立的一个平台。 Node.js 是一个事件驱动 I/O 服务端 JavaScript 环境,基于 Google 的 V8 引擎,V8 引擎执行 Javascript 的速度非常快,性能非常好。