一、变量
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<body><h1>hello world</h1><script>console.log('hello China!');//打印字符串let age = 12; //变量const num = "123";//常量console.log(typeof(num));//打印变量类型</script>
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二、对象
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<body><h1>hello world</h1><script>// 创建一个包含多个属性的对象var result = {name: "John Doe",id: 123,personlist: ["Alice", "Bob", "Charlie"]};// 打印对象的内容console.log("Result object:", result);console.log("Name:", result.name);console.log("ID:", result.id);console.log("Person list:", result.personlist);</script>
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三、数组
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<body><h1>Array Operations Example</h1><script>// 定义包含对象的数组var data = [{ id: 1, name: "Alice", score: 85 },{ id: 2, name: "Bob", score: 72 },{ id: 3, name: "Charlie", score: 90 }];// 打印第二个元素console.log("Second element:", data[1]);// 打印第二个元素的名字console.log("Second element:", data[1].name);// 遍历并打印所有元素console.log("Printing all elements:");data.forEach(function(item){console.log("ID:", item.id, "Name:", item.name, "Score:", item.score);});//转化为json输出（key也带双引号）var jsonData = JSON.stringify(data);console.log(jsonData);</script>
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