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.
42 lines
1.1 KiB
JavaScript
42 lines
1.1 KiB
JavaScript
const learningStatus = "review";
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const records = ["变量", "条件", "函数", null, "对象"];
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let optionalNote;
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const finalComment = null;
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let statusText = "";
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const finishedRecords = [];
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switch (learningStatus) {
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case "basic":
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statusText = "正在完成基础阶段";
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break;
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case "review":
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statusText = "正在进入总复习";
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break;
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case "done":
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statusText = "当前阶段已经完成";
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break;
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default:
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statusText = "状态未知";
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break;
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}
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console.log("状态说明：", statusText);
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console.log("optionalNote：", optionalNote);
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console.log("optionalNote 是否为 undefined：", optionalNote === undefined);
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console.log("finalComment：", finalComment);
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console.log("finalComment 是否为 null：", finalComment === null);
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for (let index = 0; index < records.length; index += 1) {
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const currentRecord = records[index];
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if (currentRecord === undefined || currentRecord === null) {
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console.log(`第 ${index + 1} 项为空值，停止读取。`);
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break;
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}
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finishedRecords.push(currentRecord);
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}
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console.log("停止前已读取内容：", finishedRecords);
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