1.forEach(),遍歷陣列的每個元素

    let arrFor = ['muzi','digbig','muzidigbig','lucky']
    //forEach(),遍歷陣列的每個元素
    arrFor.forEach((item,index) => {
        console.log(`${index}---${item}`)
    })

2.map(引數為回撥函式)函式，遍歷陣列每個元素，並回調操作，需要返回值，返回值組成新陣列，原陣列不變；

    let arr = [{id:1,name:'muzi'},{id:2,name:'digbig'},{id:3,name:'muzidigbig'},{id:4,name:'lucky'}]
    const arrMap = arr.map((item,index) => {
        return {
            id:item.id,
            name:item.name,
            sex:'男'
        }
    })
    console.log(arrMap)
 

3.filter(引數為回撥函式)函式：過濾通過條件的元素組成一個新陣列，原陣列不變；

    let arr = [{id:1,name:'muzi'},{id:2,name:'digbig'},{id:3,name:'muzidigbig'},{id:4,name:'lucky'}]
    const arrFilter = arr.filter((item,index) => {
        return item.id >= 2;
    })
    console.log(arrFilter)

4.some(引數為回撥函式)函式，遍歷陣列中是否有符合條件的函式，返回布林值；

    let arr = [{id:1,name:'muzi'},{id:2,name:'digbig'},{id:3,name:'muzidigbig'},{id:4,name:'lucky'}]
    const arrSome = arr.some((item,index) => {
        return item.id === 5
    })
    console.log(arrSome)

5.every(引數為回撥函式)函式，遍歷陣列是否每個元素都符合條件，返回布林值；

    let arr = [{id:1,name:'muzi'},{id:2,name:'digbig'},{id:3,name:'muzidigbig'},{id:4,name:'lucky'}]
    const arrEvery = arr.every((item,index) => {
        return item.id >= 1
    })
    console.log(arrEvery)
 

6.find()函式，陣列中的每個元素都執行這個回撥函式；返回第一個滿足條件的元素 之後的元素就不在呼叫；沒有符合的返回undefined；並沒有改變陣列的原始值。

    let arr = [{id:1,name:'muzi'},{id:2,name:'digbig'},{id:3,name:'muzidigbig'},{id:4,name:'lucky'}]
    const arrFind = arr.find((item,index) => {
        return item.id === 1
    })
    console.log(arrFind)

7.reduce(),合併二維陣列

    var twoArr = [['mu','zi'],['dig','big'],['lucky','jiji']];
    var oneArr = twoArr.reduce(function(total,currentValue){
        // console.log(total)
        return total.concat(currentValue);
    },[])
    console.log(oneArr);//["mu", "zi", "dig", "big", "lucky", "jiji"]