1)、ECMAScript是一个标准(欧洲计算机制造商协会),JavaScript只是它的一个实现,其他实现包括ActionScript(Flash脚本) 2)、ECMAScript可以为不同种类的宿主环境提供核心的脚本编程能力,即ECMAScript不与具体的宿主环境相绑定,如JavaScript的宿主环境是浏览器,AS的宿主环境是Flash。、 3)、ECMA
it would be important that they both get the same object, even ifpriorThinggets assigned over and over so that both functions share the same lexical environment. But as soon as a variable is used by any closure, it ends up in the lexical environment shared by all closures in that scope....
constname="前端小智"name="王大冶"// // TypeError: Assignment to constant variable. SyntaxError错误一般是关键字打错了,如下所示: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 va x='33';// SyntaxError: Unexpected identifier 或者,当在错误的地方使关键字时,例如await和async的使用: 代码语言:jav...
var firstRow = rows[0]; firstRow.getString("name", "").equals("Foo") js的使用: varprevRow=previous_result.getRows(); parent_job.setVariable("prevRow",prevRow); parent_job.setVariable("size",prevRow.size()); parent_job.setVariable("size1",prevRow.get(0).size()); parent_job.se...
Backticks are generally used when you need to insert variables or expressions into a string. This is done by wrapping variables or expressions with ${variable or expression}. For example, // strings example let name1 = 'Peter'; let name2 = "Jack"; let result = `The names are ${name...
functionlogName(name){varn = name ||"Mark";console.log(n);} logName();// "Mark" 3. undefined 和 null 有什么区别? 在了解 undefined 和 null 的区别之前,我们先来看看它们的相同点。 它们都属于 JavaScript 中的 7 种基本类型。 letprimitiveTypes = ...
alert(typeofmessage);//"string"alert(typeof(message));//"string"alert(typeof95);//"number" 2.2.1 Number类型 1.数值字面量:数值的固定值的表示法。 十进制:就是正常的数字 八进制:以0开头[0~7] 十六进制:0x开头[0~9及A~F] //十进制varnum = 9;//进行算数计算时,八进制和十六进制表示的数...
(); thisIsAVeryLongVariableName = 'expressionPartOne' + someMethodThatIsLong() + thisIsAnEvenLongerOtherFunctionNameThatCannotBeIndentedMore(); someValue = this.foo( shortArg, 'Some really long string arg - this is a pretty common case, actually.', shorty2, this.bar()); if (searchable...
# --global <variable-name> Updated in v6.0.0; the option is --global and --globals is now an alias. Define a global variable name. For example, suppose your app deliberately exposes a global named app and YUI, you may want to add --global app --global YUI. ...
JavaScript String Concatenation Concatenation Explained JavaScript Data Types Declare (create) stringsDeclare (create) numbersDeclare (create) an arrayDeclare (create) an objectFind the type of a variableAdding two numbers and a stringAdding a string and two numbersAn undefined variableAn empty variable...