JavaScript | Array Function (二)

1.indexOf()

// indexOf(searchElement(要查询的元素), fromIndex(起始位置)) 
let uint8 = new Uint8Array([2, 5, 9]);
uint8.indexOf(2); // 0

2.forEach()

// forEach(callbackFn, thisArg) callbackFn 执行函数；thisArg 执行 callbackFn 时用作 this 的值
const array1 = ['a', 'b', 'c'];
array1.forEach((element) => console.log(element));

3. join()

// join(separator) separator 分隔符
const a = ["Wind", "Water", "Fire"];
a.join(); // 'Wind,Water,Fire'
a.join(", "); // 'Wind, Water, Fire'
a.join(" + "); // 'Wind + Water + Fire'
a.join(""); // 'WindWaterFire'