Question

我对nodeJS还是很陌生，所以也许我做错了什么，但是我正在尝试使用节点模块json-2-csv。但是，当我遵循文档并尝试使用它时，结果却未定义。

这是我尝试使用测试数据的代码。另外，我已经运行npm install json-2-csv并检查了package.json以查看其是否存在（版本3.5.4）

let converter = require('json-2-csv');


var array = [
    {
        "configurationId": {
        "id": "4000",
        "displayName": "4000",
        "uri": "/configuration/users/4000"
        },
        "actualValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ],
        "inheritedValue": [],
        "effectiveValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ]
    },
    {
        "configurationId": {
        "id": "4001",
        "displayName": "4001",
        "uri": "/configuration/users/4001"
        },
        "actualValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ],
        "inheritedValue": [],
        "effectiveValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ]
    },
    {
        "configurationId": {
        "id": "4002",
        "displayName": "40002",
        "uri": "/configuration/users/4002"
        },
        "actualValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ],
        "inheritedValue": [],
        "effectiveValue": [
            {
            "id": "Agent",
            "displayName": "Agent",
            "uri": "/configuration/roles/Agent"
            },
            {
            "id": "SMS",
            "displayName": "SMS",
            "uri": "/configuration/roles/SMS"
            }
        ]
    }
    ];

var result = converter.json2csv(array, function(err, csv){
    console.log("Error: ", err);
}, expandArrayObjects = true);
console.log("result is...", result);

重要的一点可能是此行：

var result = converter.json2csv(array, function(err, csv){
    console.log("Error: ", err);
}, expandArrayObjects = true);

这是我的输出：

Info: Start process (12:03:39 p.m.)
the result is... undefined
Error:  null
Info: End process (12:03:39 p.m.)

我希望输出是csv格式的文本，但是从上面可以看到，我不确定。我认为我使用的方式不正确，但实际上没有经验来理解我的错误。

Answer 1

open()的参数为.json2csv。根据[npm来源]

(csv, function, options)

因此，代码将是：

options - (Optional) A JSON document specifying any of the following key value pairs:

如果要使用其他设置，则var result = converter.json2csv(array, function(err, csv){ console.log("Error: ", err); console.log("Result: ", csv); }, {expandArrayObjects:true});对象将是：

options

但是我不确定这是否会奏效不是因为语法，因为我怀疑json2csv能否将深层json转换为CSV。

此外，{ expandArrayObjects: true, .... .... }将没有数据，因为数据是通过回调传递的，并且它是一个异步函数。您需要result或在回调中使用变量。

如何正确使用json-2-csv节点模块？

1 个答案: