Javascript 如果其他参数匹配，则对数组中的参数求和

我有一个数组如下

如果资源id和startdate与其他条目匹配，我想汇总TotalHrs参数

var arr = [
    {"Id":123,
        "Subevents":[
            {"Id":225,"ParentId":123,"ResourceId":"abc","Name":"4.00","TotalHrs":"4.00","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":226,"ParentId":123,"ResourceId":"abc","Name":"4.00","TotalHrs":"4.00","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":227,"ParentId":123,"ResourceId":"xyz","Name":"8.00","TotalHrs":"8.00","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"},
            {"Id":228,"ParentId":123,"ResourceId":"xyz","Name":"8.00","TotalHrs":"8.00","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"}
        ]
    },
    {"Id":335,
        "Subevents":[
            {"Id":345,"ParentId":335,"ResourceId":"abc","Name":"2.00","TotalHrs":"2.00","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":346,"ParentId":335,"ResourceId":"pqr","Name":"6.00","TotalHrs":"6.00","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"}
        ]}];

在上例中，起始日期为“2015-08-13 00:00”的ResourceId“abc”有3个条目，总小时值为4,4,2，总计为10

我想将这3个条目的TotalHrs值更新为10

同样，ResourceId=“xyz”和StartDate=“2015-08-14 00:00”有两个这样的条目，其TotalHrs值等于8,8，即等于16

因此，如果任何其他条目与StartDate和ResourceId匹配，则生成的数组应该只更新TotalHrs值

因此，我的最终数组应该如下所示

[
    {"Id":123,
        "Subevents":[
            {"Id":225,"ParentId":123,"ResourceId":"abc","Name":"4.00","TotalHrs":"10","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":226,"ParentId":123,"ResourceId":"abc","Name":"4.00","TotalHrs":"10","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":227,"ParentId":123,"ResourceId":"xyz","Name":"8.00","TotalHrs":"16","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"},
            {"Id":228,"ParentId":123,"ResourceId":"xyz","Name":"8.00","TotalHrs":"16","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"}
        ]
    },
    {"Id":335,
        "Subevents":[
            {"Id":345,"ParentId":335,"ResourceId":"abc","Name":"2.00","TotalHrs":"10","StartDate":"2015-08-13 00:00","EndDate":"2015-08-13 23:59"},
            {"Id":346,"ParentId":335,"ResourceId":"pqr","Name":"6.00","TotalHrs":"6.00","StartDate":"2015-08-14 00:00","EndDate":"2015-08-14 23:59"}
        ]}]

---

用太多的循环。首先创建一个“ResourceId”=>“totalHrs”的对象，然后在数组中进行第二次时间循环，并根据计算出的值分配totalHrs

var totals = {};
arr.forEach(function (element) {
    if (element["Subevents"]) {
        var arr2 = element["Subevents"];
        arr2.forEach(function (element) {
            totals[element["ResourceId"] + element["StartDate"]] = totals[element["ResourceId"] + element["StartDate"]] || 0;
            totals[element["ResourceId"] + element["StartDate"]] += parseInt(element["TotalHrs"]);
        })
    }
});

arr.forEach(function (element) {
    if (element["Subevents"]) {
        var arr2 = element["Subevents"];
        arr2.forEach(function (element) {
            element["TotalHrs"] = totals[element["ResourceId"] + element["StartDate"]];
        })
    }
})

---

此解决方案使用一个临时对象来计算分组项的总和：

var arr=[{“Id”：123，“Subevents”：[{“Id”：225，“ParentId”：123，“ResourceId”：“abc”，“Name”：“4.00”，“TotalHrs”：“4.00”，“StartDate”：“2015-08-13 00:00”，“EndDate”：“2015-08-13 23:59”}，{“Id”：226，“ParentId”：123，“ResourceId”：“abc”，“Name”：“4.00”，“TotalHrs”：“4.00”，“StartDate”：“2015-08-13 00:00”，“EndDate”：“2015-08-13 23:59”}，{“Id”：227，“ParentId”：123，“ResourceId”：“xyz”，“Name”：“8.00”，“TotalHrs”：“8.00”，“StartDate”：“2015-08-14 00:00”，“EndDate”：“2015-08-14 23:59”}，{“Id”：228，“ParentId”：123，“ResourceId”：“xyz”，“Name”：“8.00”，“TotalHrs”：“8.00”，“StartDate”：“2015-08-14 00:00”，“EndDate”：“2015-08-14 23:59”}，{“Id”：335，“子事件”{“Id”：：345，“家长Id”：335，“资源Id”：“abc”，“姓名”：“2.00”，“总小时数”：“2.00”，“开始日期”：“2015-08-13 00:00”，“结束日期”：“2015-08-13 23:59”}，{“Id”：346，“家长Id”：335，“资源Id”：“pqr”，“姓名”：“6.00”，“总小时数”：“6.00”，“开始日期”：“2015-08-14 00:00”，“结束日期”：“2015-08-14 23:59”}，
温度={}；
arr.forEach（功能（a）{
a、 子事件。forEach（函数（b）{
temp[b.ResourceId]=temp[b.ResourceId]| |{}；
temp[b.ResourceId][b.StartDate]=（temp[b.ResourceId][b.StartDate]| 0）++b.TotalHrs；
});
});
arr.forEach（功能（a）{
a、 子事件。forEach（函数（b）{
b、 TotalHrs=温度[b.ResourceId][b.StartDate]；
});
});
document.write（'temp:'+JSON.stringify（temp，0，4）+''）；
document.write（'arr:'+JSON.stringify（arr，0，4）+''）谢谢，但是代码中没有提到起始日期，因为如果我更改ID为345的记录的起始日期，它将不会给出正确的结果。请注明我的答案，以包括
起始日期