javascript - 如果其他参数匹配，则对数组中的参数求和

Question

我有一个如下的数组

如果资源 ID 和开始日期与其他条目匹配，我想对 TotalHrs 参数求和。

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,
        "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"}
        ]}];

在上面的示例中，ResourceId“abc”，开始日期为“2015-08-13 00:00”，有 3 个条目，TotalHrs 值为 4,4,2，总和为 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 2 个这样的条目，TotalHrs 值等于 8,8，等于 16。

因此，如果任何其他条目与 StartDate 和 ResourceId 匹配，我的结果数组应该只更新 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"}
        ]}]

Answer 1

用太循环来做。首先创建一个带有 'ResourceId' => 'totalHrs' 的对象，第二次循环遍历数组并根据计算值分配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"]];
        })
    }
})