js map的使用 

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<body>

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<script>
    let data = [{
            "usedNum": 1,
            "noUsedNum": 9,
            "sEnterpriseQutos": {
                "id": 5,
                "serviceTag": "VPC",
                "serviceTagNum": 10,
                "projectSetId": "8"
            }
        },
        {
            "usedNum": 1,
            "noUsedNum": 12,
            "sEnterpriseQutos": {
                "id": 6,
                "serviceTag": "ECS",
                "serviceTagNum": 13,
                "projectSetId": "8"
            }
        },
        {
            "usedNum": 1,
            "noUsedNum": 12,
            "sEnterpriseQutos": {
                "id": 7,
                "serviceTag": "ECS",
                "serviceTagNum": 13,
                "projectSetId": "8"
            }
        },
    ]

    let nowData = data.map(item => {
        return {
            usedNum: item.usedNum,
            noUsedNum: item.noUsedNum,
            serviceTag: item.sEnterpriseQutos.serviceTag,
            sEnterpriseQutos: {
                id: item.sEnterpriseQutos.id,
                sex: item.sEnterpriseQutos.id == 5 ? '男' : item.sEnterpriseQutos.id == 6 ? '女' : '保密',
                serviceTagNum: item.sEnterpriseQutos.serviceTagNum,
                projectSetId: item.sEnterpriseQutos.projectSetId,
            }
        }
    })
    console.log("nowData")
    console.log(nowData)
    let arr = [1, '2', 3, '4', '5', '6.1', 6.2]

    let newArr = arr.map(Number)
    // parseInt不能直接使用
    let newArr2 = arr.map(str => parseInt(str))
    console.log("newArr")
    console.log(newArr)
    console.log(newArr2)


    let numbers = [1, 2, 3, 4];
    let filteredNumbers = numbers.map((num, index) => {
        if (index < 2) {
            return num;
        }else{
            return 6
        }
    });
    console.log("filteredNumbers")
    console.log(filteredNumbers)
</script>

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posted @ 2020-11-27 15:48  lzhflzjx  阅读(111)  评论(0)    收藏  举报