877acb5a8f
- Implemented exercises for array high-order methods, memory and execution, switch statements, and final review. - Added starter and answer files for each exercise to facilitate learning. - Created a runner HTML file to execute JavaScript code and display console outputs. - Updated README files to include exercise objectives, tasks, and usage instructions.
29 lines
800 B
JavaScript
29 lines
800 B
JavaScript
console.log("var 声明前：", lessonType);
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var lessonType = "JavaScript";
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console.log("var 声明后：", lessonType);
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// console.log("let 声明前：", chapterType);
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// let 在声明前处于暂时性死区，直接访问会报错。
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function compareScope() {
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if (true) {
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var lessonName = "变量";
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let chapterName = "作用域";
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const stage = "进阶";
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console.log("块内：", lessonName, chapterName, stage);
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}
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console.log("块外仍能访问 var：", lessonName);
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// console.log(chapterName);
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// chapterName 是 let 声明的块级作用域变量，离开 if 代码块后就不能访问。
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}
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compareScope();
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const level = "核心阶段";
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console.log("const 初始值：", level);
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// level = "下一阶段";
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// const 不能被重新赋值，否则会报错。
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