set 集合实践
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>set集合实践</title> </head> <body> <div id="ad"> </div> <div></div> <script> let arr = [1,2,2,3,1,4,5]; //数组去重 let arr2 = [... new Set(arr)]; console.log(arr2); //交集 let arr3 = [2,3,2,4,5]; let arr4 = [4,5,6,7]; let arrSet4 = new Set(arr4); let result = arr3.filter(item=>arrSet4.has(item)); console.log(result); //并集 let arr5 = [2,3,2,4,5]; let arr6 = [4,5,6,7]; let result2 = [...new Set([...arr5, ...arr6])]; console.log(result2); //差集 let arr7 = [2,3,2,4,5]; let arr8 = [4,5,6,7]; let arrSet8 = new Set(arr8); let result3 = [...new Set(arr7.filter(item=>!arrSet8.has(item)))]; console.log(result3); </script> </body> </html>