Question

我有一个json对象数组，我需要按四个数组将它们组合在一起以创建单个对象。最终，我的目标是在SQL Sever中使用OPENJSON将值插入表中，每个对象都是一行。

似乎应该足够简单。我已经在网上搜索了很多东西，并且遇到了_.groupBy（），$。extend（true，{}，x，y）等各种事物。等等，但是似乎都没有我想要的。

我有以下JSON对象数组：

[{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"04/29/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}, 
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"04/30/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}, 
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"05/01/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}, 
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"05/02/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}, 
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"05/03/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}]

我需要这样分组：

Object {
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"04/29/2019"},
{"name":"intStps","value":"1"},
{"name":"intPkgs","value":"2"}
},
Object {
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"04/30/2019"},
{"name":"intStps","value":"1"},
{"name":"intPkgs","value":"2"}
},
Object {
{"name":"locMLR","value":"6485183463415278686"}, 
{"name":"dayDate","value":"05/01/2019"},{"name":"intStps","value":"1"}, 
{"name":"intPkgs","value":"2"}
}

Answer 1

您可能想要一个类似chunk的函数，该函数需要块大小和一个数组，并将元素分组为该大小的块：

const chunk = (n, arr, res = []) => arr.length == 0
  ? res
  : chunk (n, arr.slice(n), res.concat([arr.slice(0, n)]))

const arr = [{"name": "locMLR", "value": "6485183463415278686"}, {"name": "dayDate", "value": "04/29/2019"}, {"name": "intStps", "value": "1"}, {"name": "intPkgs", "value": "2"}, {"name": "locMLR", "value": "6485183463415278686"}, {"name": "dayDate", "value": "04/30/2019"}, {"name": "intStps", "value": "1"}, {"name": "intPkgs", "value": "2"}, {"name": "locMLR", "value": "6485183463415278686"}, {"name": "dayDate", "value": "05/01/2019"}, {"name": "intStps", "value": "1"}, {"name": "intPkgs", "value": "2"}, {"name": "locMLR", "value": "6485183463415278686"}, {"name": "dayDate", "value": "05/02/2019"}, {"name": "intStps", "value": "1"}, {"name": "intPkgs", "value": "2"}, {"name": "locMLR", "value": "6485183463415278686"}, {"name": "dayDate", "value": "05/03/2019"}, {"name": "intStps", "value": "1"}, {"name": "intPkgs", "value": "2"}]

console.log(chunk(4, arr))

有许多替代方法可以编写此代码。但是，这种递归解决方案简单明了，并且当您的JS引擎执行尾部调用优化时，它应该相对有效。

更新

如果要执行此操作而无需递归调用，可以使用reduce折叠数组，如下所示：

const chunk = (n, xs) => xs.reduce(
  (a, x, i) => i % n == 0 
    ? a.concat([[x]]) 
    : a.slice(0, -1).concat([a.slice(-1)[0].concat(x)]), 
  []
)

但是对我来说，它的可读性要差很多。

Answer 2

您并不是真正意义上的分组，我会做这样的事情：

const originalData = [
    {
        "name": "locMLR",
        "value": "6485183463415278686"
    },
    {
        "name": "dayDate",
        "value": "04/29/2019"
    }, {
        "name": "intStps",
        "value": "1"
    },
    {
        "name": "intPkgs",
        "value": "2"
    },
    {
        "name": "locMLR",
        "value": "6485183463415278686"
    },
    {
        "name": "dayDate",
        "value": "04/30/2019"
    }, {
        "name": "intStps",
        "value": "1"
    },
    {
        "name": "intPkgs",
        "value": "2"
    },
    {
        "name": "locMLR",
        "value": "6485183463415278686"
    },
    {
        "name": "dayDate",
        "value": "05/01/2019"
    }, {
        "name": "intStps",
        "value": "1"
    },
    {
        "name": "intPkgs",
        "value": "2"
    },
    {
        "name": "locMLR",
        "value": "6485183463415278686"
    },
    {
        "name": "dayDate",
        "value": "05/02/2019"
    }, {
        "name": "intStps",
        "value": "1"
    },
    {
        "name": "intPkgs",
        "value": "2"
    },
    {
        "name": "locMLR",
        "value": "6485183463415278686"
    },
    {
        "name": "dayDate",
        "value": "05/03/2019"
    }, {
        "name": "intStps",
        "value": "1"
    },
    {
        "name": "intPkgs",
        "value": "2"
    }
];

const groupedData = [];
let groupedItem = [];
originalData.forEach((data, index) => {
    groupedItem.push(data);
    if (index % 4 === 3) {
        groupedData.push(groupedItem);
        groupedItem = [];
    }
});
console.log(groupedData);

如何将json对象数组的倍数分组为新对象？

2 个答案:

更新