jquery从循环推入多维数组

Question

我正在尝试通过执行以下操作在 for 循环中创建一个数组：

var newArr = [];
for(var j=0; j < ChargeTypes.ChargeType.length; j++){
    var ChargeTypeId = ChargeTypes.ChargeType[j].ChargeTypeId;
    var Date = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].Date;
    var NoOfRoomsAvailable = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].NoOfRoomsAvailable;
    newArr.push({ChargeTypeId},{Date});
    newArr.push({ChargeTypeId},{NoOfRoomsAvailable});
};
alert( JSON.stringify(newArr) );

这是在创造：

[
    {"ChargeTypeId":"1"},
    {"Date":"2017-12-28"},
    {"ChargeTypeId":"1"},
    {"NoOfRoomsAvailable":"0"},
    {"ChargeTypeId":"23"},
    {"Date":"2017-12-28"},
    {"ChargeTypeId":"23"},
    {"NoOfRoomsAvailable":"3"}
]

但我希望得到这样的东西：

[1] //ChargeTypeID
    {
        Date:"2017-12-28",
        NoOfRoomsAvailable:"0"
    },
[23] //ChargeTypeID
    {
        Date:"2017-12-28",
        NoOfRoomsAvailable:"3"
    }

我试过用这个：

newArr[ChargeTypeId].push("Date",Date);
newArr[ChargeTypeId].push("NoOfRoomsAvailable",NoOfRoomsAvailable);

但我收到此错误：

TypeError: newArr[ChargeTypeId] 未定义

我显然遗漏了一些东西，这可能是一些小东西，哈哈，但如果有人能帮助我，那就太好了。

Answer 1

您面临的问题是 JS 不像其他一些语言那样支持关联数组。相反，JS 有对象，你必须忍受它。此时您可以做的最好的事情是创建：

$obj = [
    {"ChargeTypeId":"1", "Date":"2017-12-28", "NoOfRoomsAvailable":"0"},
    {"ChargeTypeId":"23", "Date":"2017-12-28", "NoOfRoomsAvailable":"3"}
]

然后您可以将 ID 引用为obj.ChargeTypeId。这可以通过以下方式实现：

var newArr = [];
for(var j=0; j < ChargeTypes.ChargeType.length; j++){
    var Date = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].Date;
    var NoOfRoomsAvailable = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].NoOfRoomsAvailable;
    newArr.push({ChargeTypeId,Date,NoOfRoomsAvailable});
};

Answer 2

push 只是将一个值添加到（平面）数组的末尾。将多个参数传递给push 不会在数组中引入额外的级别。同样，数组索引是纯数字和顺序的，从 0 开始。如果您有自定义的稀疏 ID（在您的情况下也是字符串），则不能将它们用作索引来检索/存储数组中的值。

请尝试以下方法：

var newArr = [];

for(var j = 0; j < ChargeTypes.ChargeType.length; j++){
    var chargeType = ChargeTypes.ChargeType[j];
    var chargeAttribute = chargeType.Charge[0]['@attributes'];
    var chargeDetails = {
        ChargeTypeId : chargeType.ChargeTypeId,
        Date : chargeAttribute.Date,
        NoOfRoomsAvailable : chargeAttribute.NoOfRoomsAvailable
    };

    newArr.push(chargeDetails);
};

您在此处的结果将与此类似，这是典型的类似 JSON 的结构：

[
    {
        ChargeTypeId : "1",
        Date : "2017-12-28",
        NoOfRoomsAvailable : "0"
    },
    {
        ChargeTypeId : "23",
        Date : "2017-12-28",
        NoOfRoomsAvailable : "3"
    }
]

Answer 3

这应该可以工作

var newArr = [];
for(var j=0; j < ChargeTypes.ChargeType.length; j++){
    var ChargeTypeId = ChargeTypes.ChargeType[j].ChargeTypeId;
    var Date = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].Date;
    var NoOfRoomsAvailable = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].NoOfRoomsAvailable;
    newArr[parseInt(ChargeTypeId)] = {
        "Date": Date,
        "NoOfRoomsAvailable": NoOfRoomsAvailable 
    };
};

Answer 4

您只需要创建new array 或ChargeTypeId 即可允许推送。因为目前newArr[ChargeTypeId] 没有找到所以它给你错误。推送前添加newArr[ChargeTypeId] = [];。

试试这个：

var newArr = [];
for(var j=0; j < ChargeTypes.ChargeType.length; j++){
    var ChargeTypeId = ChargeTypes.ChargeType[j].ChargeTypeId;
    var Date = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].Date;
    var NoOfRoomsAvailable = ChargeTypes.ChargeType[j].Charge[0]['@attributes'].NoOfRoomsAvailable;
    newArr[ChargeTypeId] = [];
    newArr.push({ChargeTypeId},{Date});
    newArr.push({ChargeTypeId},{NoOfRoomsAvailable});
};
alert( JSON.stringify(newArr) );