let arr1 = ['kk', 'jo', 'll']; if (arr1.includes("kk")) {//【ɪnˈkluːz】 console.log("找到了", arr1.includes("kk"));//true } else { console.log("没有", arr1.includes("kk")); } ================================================================= let arr2 = ['kk', 'jo', 'll']; if (arr2.includes("kk", 1)) { //第二个参数,表示从数组中下标为1包含1处开始找 console.log("找到了", arr2.includes("kk")); } else { console.log("没有", arr2.includes("kk"));//false }