Question

我想在记录数组搜索后更新变量和数组项，并想知道在Javascript中执行它的最佳方法是什么。

在这种情况下，如果在变量和区域项之间找到匹配项，则应将邮政编码项附加到变量。

对于数组项也需要做同样的事情，但我认为for循环在这种情况下最有效，因为需要以某种方式访问每个单独的项。

顺便说一句，由于我的程序性质，总会有匹配。 此外，我需要能够区分singleAddress和multipleAddresses变量。

希望这段代码能更好地解释一下：

// before search 
var singleAddress = "Mount Farm";
var multipleAddresses = ["Elfield Park", "Far Bletchley", "Medbourne", "Brickfields"];

// this is the record which the search needs to be run against
plot = [{
    postcode: "MK1",
    area: "Denbigh, Mount Farm",
}, {
    postcode: "MK2",
    area: "Brickfields, Central Bletchley, Fenny Stratford, Water Eaton"
}, {
    postcode: "MK3",
    area: "Church Green, Far Bletchley, Old Bletchley, West Bletchley",
}, {
    postcode: "MK4",
    area: "Emerson Valley, Furzton, Kingsmead, Shenley Brook End, Snelshall West, Tattenhoe, Tattenhoe Park, Westcroft, Whaddon, Woodhill",
}, {
    postcode: "MK5",
    area: "Crownhill, Elfield Park, Grange Farm, Oakhill, Knowlhill, Loughton, Medbourne, Shenley Brook End, Shenley Church End, Shenley Lodge, Shenley Wood",
}]

// after search is run then:
// var singleAddress = "Mount Farm, MK1"
// var multipleAddresses = ["Elfield Park, MK5", "Far Bletchley, MK3", "Medbourne, MK5", "Brickfields, MK2"]

Fiddle here

Answer 1

好的，您无法轻松更改原始数据格式。实际记录有多大，多久更新一次？因为如果它不是很大并且每秒没有多次改变并且您要进行多次查找，那么创建我提到的映射然后再读取会更有效率从它，而不是每次都通过原始结构。我将在这个答案中假设这样。希望它有所帮助。

此代码中的另一个假设是：每个区域只有一个邮政编码。

function convertPlot(plot)
{
    var mapping={}
    plot.forEach(function (r){
        var locations=r.area.split(/,\s*/)
        for(var i=0, loc; loc=locations[i]; i++)
            mapping[loc]=r.postcode
    })
    return mapping
}

当你得到情节时，只需这样做：

mapping=convertPlot(plot)

然后查找功能变得微不足道了：

function lookup(adr)
{
    if('string' == typeof adr)
        return adr+", "+mapping[adr]
    if(('object' == typeof adr) && adr instanceof Array)
        return adr.map(lookup)
    throw new TypeError("cannot look up something that isn't a string or array or strings")
}

在记录数组搜索后附加变量和数组项

1 个答案: