52 lines
1.7 KiB
JavaScript
52 lines
1.7 KiB
JavaScript
const numbers = [15, 8, 23, 4, 42, 16, 7];
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const students = [
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{ name: '张三', score: 85 },
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{ name: '李四', score: 62 },
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{ name: '王五', score: 91 }
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];
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console.log('1. slice() - 数组切片');
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const sliced = numbers.slice(1, 4);
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console.log('numbers.slice(1, 4):', sliced);
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console.log('\n2. filter() - 筛选元素');
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const evenNumbers = numbers.filter(numbers => numbers % 3 == 0);
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console.log('偶数:', evenNumbers);
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console.log('\n3. find() - 查找元素');
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const findScore = students.find(student => student.score > 90);
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console.log('分数>90的学生:', findScore);
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console.log('\n4. findIndex() - 查找索引');
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const index = numbers.findIndex(numbers => numbers > 20);
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console.log('第一个>20的数的索引:', index);
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console.log('\n5. every() - 所有元素满足条件');
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const allPassed = students.every(student => student.score >= 60);
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console.log('所有学生都及格:', allPassed);
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console.log('\n6. some() - 至少一个满足条件');
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const hasHighScore = students.some(student => student.score > 90);
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console.log('有高分学生:', hasHighScore);
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console.log('\n7. unshift() - 开头添加');
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const arr = [2, 3];
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arr.unshift(1);
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console.log('添加后:', arr);
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console.log('\n8. splice() - 添加删除');
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const colors = ['red', 'green', 'blue'];
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colors.splice(1, 1, 'yellow');
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console.log('替换后:', colors);
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console.log('\n9. sort() - 排序');
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const sortedAsc = [...numbers].sort((a, b) => a - b);
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const sortedDesc = [...numbers].sort((a, b) => b - a);
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console.log('升序:', sortedAsc, '降序:', sortedDesc);
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console.log('\n10. reduce() - 累加');
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const sum = numbers.reduce((total, num) => total + num, 0);
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console.log('数组求和:', sum);
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