reverse() 不是一个函数

Question

我在 javascript 中编写了一个函数来计算我们的票务系统的库存。作为输入，我得到以下输入：

[{key:"10-09-2017", value:{countCreatedTickets: 98, countOpenTickets: 13, countSolvedTickets: 61}},
 {key:"12-09-2017", value:{countCreatedTickets:51,  countOpenTickets: 14, countSolvedTickets: 33}}
]

我使用的函数是：

function funnelCalulation(ds){
    var stock = 0, stockCalulations = []
    console.info('-------  funnelCalulation -------')
    console.info(ds)
    ds = ds.reverse()

    for(var i = 0; i < ds.length; i++ ){
        if (i == 0){
            stock = ( ds[i].value.countCreatedTickets + ds[i].value.countOpenTickets ) - ds[i].value.countSolvedTickets
            stockCalulations.push({datum: ds[i].key, createdTickets: ds[i].value.countCreatedTickets, opentTickets: ds[i].value.countOpenTickets, ticketStock: stock })

        }
        if (i > 0){
            stock = ( ds[i].value.countCreatedTickets + ds[i].value.countOpenTickets + stock ) - ds[i].value.countSolvedTickets
            stockCalulations.push({datum:ds[i].key, createdTickets: ds[i].value.countCreatedTickets, opentTickets: ds[i].value.countOpenTickets, ticketStock: stock })
        }
    }

    return stockCalulations[ds.length-1]
}

我按如下方式调用该函数：

var stockValues = funnelCalulation(values)
            console.info('  ---- > stockValues  <--------')
            console.info(stockValues)

console.info(ds) 返回以下输出：

如果我输入 typeof ds 它会返回一个对象。结果是该函数工作正常，但返回值时返回以下错误：

ticketsGraphs.js:49 Uncaught TypeError: ds.reverse is not a function
    at funnelCalulation (ticketsGraphs.js:49)
    at Object.success (createWidgets.js:121)
    at i (jquery-3.2.1.min.js:2)
    at Object.fireWith [as resolveWith] (jquery-3.2.1.min.js:2)
    at A (jquery-3.2.1.min.js:4)
    at XMLHttpRequest.<anonymous> (jquery-3.2.1.min.js:4)

我把完整的代码放在下面的jsfilde中：

https://jsfiddle.net/Erik_Hoeven/Lahuc4oe/

Answer 1

您需要向 .reverse() 传递一个数组。

 function funnelCalulation(ds){
        var stock = 0, stockCalulations = []
        console.info('-------  funnelCalulation -------')
        console.info(ds)
        ds = ds.toString().split('').reverse().join('')

        for(var i = 0; i < ds.length; i++ ){
            if (i == 0){
                stock = ( ds[i].value.countCreatedTickets + ds[i].value.countOpenTickets ) - ds[i].value.countSolvedTickets
                stockCalulations.push({datum: ds[i].key, createdTickets: ds[i].value.countCreatedTickets, opentTickets: ds[i].value.countOpenTickets, ticketStock: stock })

            }
            if (i > 0){
                stock = ( ds[i].value.countCreatedTickets + ds[i].value.countOpenTickets + stock ) - ds[i].value.countSolvedTickets
                stockCalulations.push({datum:ds[i].key, createdTickets: ds[i].value.countCreatedTickets, opentTickets: ds[i].value.countOpenTickets, ticketStock: stock })
            }
        }

        return stockCalulations[ds.length-1]
    }