var decArray = [23, 255, 122 ,5, 16, 99]; var hexArray = decArray.map(function(element) { return element.toString(16); }); console.log(hexArray); 对从qureySelector返回的NodeList使用forEach和call方法 var cells = document.querySelectorAll("td + td"); [].foreach.call(cells, funct...
associativeArray["key"] = "value"; 访问键值对: 代码语言:javascript 复制 var value = associativeArray["key"]; 删除键值对: 代码语言:javascript 复制 delete associativeArray["key"]; 遍历关联数组: 代码语言:javascript 复制 for (var key in associativeArray) { var value = associativeArray[key]; co...
To access arrays inside arrays, use a for-in loop for each array: Example for(letiinmyObj.cars) { x +=""+ myObj.cars[i].name+""; for(letjinmyObj.cars[i].models) { x += myObj.cars[i].models[j]; } } Try it Yourself...
Float32Array, Float64Array, Int8Array, Int16Array, Int32Array, Uint8Array, Uint16Array, Uint32Array, Uint8ClampedArray, Atomics, JSON, Math, Reflect ]; objects.forEach(o => set.add(o)); for(var i = 0; i < objects.length; i++) { var o = objects[i] for(var p of Object....
数组的定义: var colors = new Array(20); var colors = new Array('red'); // ['red'] var colors = ['red'...function(item, index, array){}); 所有元素返回true则返回true colors.filter(function(item, index, array){}); 返回为true的元素组成的数组...colors.forEach(function(item, index...
log(array[i]) } // 高阶函数 forEach(array, item => { console.log(item) }) 闭包 前一小节中我们通过仿写forEach和filter来简单理解了一下函数作为参数下来我们通过几个函数作为返回值的例子来理解下闭包: 下面的例子:如果我们在一个函数里面又返回了一个函数,并且在我们访问的这个函数的内部又访问了...
JavaScript supports associative array syntax, but it doesn’t really have associative arrays. They are useless, because you can use objects. Let’s create a simple object: var movie = { title : '2001: A space Odissey', director : 'Stanley Kubrick', year : 1968 }; Here, we define an ...
You can also use the Array.forEach() function: const fruits = ["Banana", "Orange", "Apple", "Mango"]; let text = ""; fruits.forEach(myFruits); text += ""; document.getElementById("demo").innerHTML = text; function myFruits(value) { text += "" + value + ""; } 🔺 Add...
Array(数组) Date(日期) RegExp(正则表达式) null(空) undefined(未定义) JavaScript 还有一种内置的但是,如果我们继续使用上面的分类,事情便容易得多;所以,现在,我们先讨论上面这些类型。 数字 根据语言规范,JavaScript 采用“遵循 IEEE 754 标准的双精度 64 位格式”("double-precision 64-bit format IEEE 754...
The label is a string to be used as the label for the entry in the info log, and the optional argument context is an object that has a variable for each property of the info message. Use this function to show information about the execution of scripts. This is particularly useful for...