Question

所以我有一个包含两个不同数组的数组：

 var _staticRoutingTable = [];

 function StaticRoute(directory, extentions) {
        this.dir = directory;
        this.extentions = extentions;
 }

_staticRoutingTable.push(new StaticRoute(["htmlfolder"], ["./html"]));
_staticRoutingTable.push(new StaticRoute(["somefolder"], ["./html","./txt","./css"]));

假设我只想获得“dir”数组，其中文件夹的名称是“somefolder”。

所以我不想要这样的smth，因为......：

 return _staticRoutingTable.forEach(function callb(route) {           
       return route.dir.filter(function callb(directory) {directory=="somefolder" })
 });

....我得到了dir + extention数组。我怎样才能过滤一个数组（在本例中为“dir”）。

Answer 1

我仍然不确定我是否正确理解了您的问题 - 但要获得像['something']这样的数组，您可以使用find：

var _staticRoutingTable = [];

function StaticRoute(directory, extentions) {
    this.dir = directory;
    this.extentions = extentions;
}

_staticRoutingTable.push(new StaticRoute(["htmlfolder"], ["./html"]));
_staticRoutingTable.push(new StaticRoute(["somefolder"], ["./html","./txt","./css"]));

let foo = _staticRoutingTable.find(function (a) {
    return a.dir.indexOf("somefolder") > -1;
});
if (foo) {
    console.log(foo.dir);    
}

请注意，这将仅返回第一个匹配项。如果您感兴趣的是多个可能的匹配项，则可以切换过滤器以进行查找，然后使用生成的数组。

但是，当您搜索“somefolder”并想要返回像['somefolder']这样的数组时，它会更容易做到

console.log(['somefolder']);

...

这适用于多个匹配：

    var _staticRoutingTable = [];

    function StaticRoute(directory, extentions) {
        this.dir = directory;
        this.extentions = extentions;
    }

    _staticRoutingTable.push(new StaticRoute(["htmlfolder"], ["./html"]));
    _staticRoutingTable.push(new StaticRoute(["somefolder"], ["./html","./txt","./css"]));

    let foo = _staticRoutingTable.filter(function (a) {
        return a.dir.indexOf("somefolder") > -1;
    });
    foo.forEach(function (v) { console.log(v.dir); });

过滤另一个数组中的一个数组

1 个答案: