Question

我有2个2D数组，想将a [0]与b [0]合并

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任何人都可以显示如何吗？

Answer 1

您可以使用spread syntax

Spread语法允许迭代器在0+ 参数是可以预期的。

var a=[["a","b","c"],["d","e","f"]];
var b=[["1","2","3"],["4","5","6"]];

//if you are trying to achieve all elements in single array then
var result = [...a[0], ...b[0]];
console.log(result);

//if you are trying to achieve single element from first array and all from other then
var result = [...a[0][0], ...b[0]];
console.log(result);

关于Spread syntax的好文章

Answer 2

在 docs 中，Array.splice的语法为

array.splice（start [，deleteCount [，item1 [，item2 [，...]]]]）

如您所见，您可以在数组中添加多个元素，例如arr.splice(0,0,4,5)，您要将2个值（4和5）添加到数组中。使用b[0]作为第三个参数，您将整个数组添加到特定索引处。要添加单个值，您需要散布数组的值。您可以使用spread syntax。这样arr.splice(0,0,...[1,2])将成为arr.splice(0,0,1,2)

var a=[["a","b","c"],["d","e","f"]];
var b=[["1","2","3"],["4","5","6"]];
a[0].splice(1,2,...b[0])
console.log(a[0]);

多维数组拼接返回嵌套数组JavaScript

2 个答案: