创建阶段 executionContextObj={//作用域链'scopeChain':{/* 变量对象 + 所有父级执行上下文中的变量对象 */},// 变量对象'variableObject':{/* 函数参数 / 参数, 内部变量以及函数声明 */},'this':{}} 2 - 变量对象 (Variable Object) 可能用到的知识点:[JS] 声明提升 (变量 函数声明) 2.1 - 创建...
mykeyValues){//没有则跳出if(!obj["mykey"]){returnmykeyValues;}else{//有就放入mykeyValues.push(obj["mykey"]);//再次递归varkeys=Object.keys(obj);keys.forEach(function(i){getMykey(obj[i],mykeyValues
console.log(pet); // {type:'Dog', name:'Tommy'} 17,Object[key]简写 考虑一个验证函数:functionvalidate(values) {if(!values.first)returnfalse;if(!values.last)returnfalse;returntrue; }console.log(validate({first:'Bruce',last:'Wayne'}));// true假设当需要不同域和规则来验证,能否编写一个通...
API is now exposed on the global object, making it easier to use without explicit imports. This API provides a powerful pattern matching system for URLs, similar to how regular expressions work for strings. This feature was a contribution by Jonas Badalič in#56950. ...
parse (default: {})— pass an object if you wish to specify some additional parse options. sourceMap (default: false)— pass an object if you wish to specify source map options. toplevel (default: false)— set to true if you wish to enable top level variable and function name mangling...
classProxySandBox{proxyWindow;isRunning=false;active(){this.isRunning=true;}inactive(){this.isRunning=false;}constructor(){constfakeWindow=Object.create(null);this.proxyWindow=newProxy(fakeWindow,{set:(target,prop,value,receiver)=>{if(this.isRunning){target[prop]=value;}},get:(target,prop,...
functionfoo(){this.variable="potential accidental global";}// Foo called on its own, this points to the global object (window)// rather than being undefined.foo(); 或者匿名函数里的this,在非严格模式也指向global。可以通过lint检查或者开启严格模式来避免这些显而易见的问题 ...
CLI: --generatedCode.objectShorthand/--no-generatedCode.objectShorthand 默认: false该选项表示当属性名称与值匹配时,是否允许在对象中使用别名。// inputconst foo = 1;export { foo, foo as bar };// 设置 objectShorthand 为 false 的系统输出System.register('bundle', [], function (exports) { 'use...
t.objectProperty(key, value) ); break; } } }); const children = node.children.map((e) => { switch(e.type) { case 'JSXElement': { return handleJSXElement(e); // 如果子元素有 JSX,便利 handleJSXElement 自身 } case 'JSXText': { ...
或者可以使用短路求值方法:const variable2 = variable1 || 'new'; 3.声明变量简写方法 代码语言:javascript 代码运行次数:0 运行 AI代码解释 letx;lety;letz=3; 简写方法:let x, y, z=3; 4.if存在条件简写方法 if (likeJavaScript === true) ...