//typeof操作符的操作数可以是变量(message)、也可以是数值字面量,操作符返回下列字符串"undefined":这个值未定义"boolean":布尔值"string":字符串"number":数值"object":对象或null"function":函数 eg:varmessage="some string"; alert(typeofmessage);//"string"alert(typeof(message));//"string"alert(typ...
value){if(value===18){console.log("Congratulations! You are of legal age");Reflect.set(target,property,value);returntrue;}}});person.age=18;if(value<13&&value>99){thrownewError('The age should be between 13 and 99')}else{Reflect.set(target,property,value)}...
Math.random() returns a random number between 0 (included) and 1 (excluded)How to return a random integer between 0 and 9 (both included)How to return a random integer between 0 and 10 (both included)How to return a random integer between 0 and 99 (both included)How to return a rand...
接下来,让我们看看这个操作符与默认参数的区别。 functiongameSettingsWithNullish(options){options.gameSpeed??=1options.gameDiff??='easy'returnoptions}functiongameSettingsWithDefaultParams(gameSpeed=1,gameDiff='easy'){return{gameSpeed,gameDiff}}gameSettingsWithNullish({gameSpeed:null,gameDiff:null})// =...
chance.js - Random generator helper in JavaScript. Can generate numbers, strings etc. odometer - Smoothly transitions numbers with ease. accounting.js - A lightweight JavaScript library for number, money and currency formatting - fully localisable, zero dependencies. money.js - A tiny (1kb) Jav...
1.常规函数 (1)alert函数:显示一个警告对话框,包括一个OK按钮。 (2)confirm函数:显示一个确认对话框,包括OK、Cancel按钮。 (3)escape函数:将字符转换成Unicode码。 (4)eval函数:计算表达式的结果。 (5)isNaN函数:测试是(true)否(false)不是一个数字。
padding[number]: Padding between bars. Default:0.1. roughness[number]: Roughness level of chart. Default:1. simplification[number]: Chart simplification. Default0.2. stroke[string]: Color of bars' stroke. Default:black. strokeWidth[number]: Size of bars' stroke. Default:1. ...
Use a combination of JavaScript Math methods: random to generate a random value between 0 and 1, which is then multiplied by 255, and floor to truncate the number. var randomNumber = Math.floor(Math.random() * 255); Discussion The random method generates a random number between 0 and 1...
percent is a number between 0 and 1 representing the progress percentage. transferredBytes is the number of bytes transferred so far. totalBytes is the total number of bytes to be transferred. This is an estimate and may be 0 if the total size cannot be determined. chunk is an instance of...
step()方法的参数表示动作:0 表示直行,1 表示向左转,2 表示向右转。step()方法的返回值具有以下字段: state—动作后立即棋盘的新状态,表示为具有两个字段的普通 JavaScript 对象: s—蛇占据的方块,以[x, y]坐标数组形式表示。此数组的元素按照头部对应第一个元素,尾部对应最后一个元素的顺序排列。