为什么这个不为空的数组返回为空？

Question

Really struggling to understand why my conditions are resolving that the array is empty when it isn't!

Here is the code:

const info = [
    [
        {
            "Post": 7
        }
    ]
]

let Result;
     if (!Array.isArray(info[0][0]) || info[0][0].length === 0) {
        Result = {"Error": "No info"}
     }

Even though info has data in it, I still get back Result as {"Error: "No info"} .

Why are my if conditions not working properly? I think its something to do with the .Array.isArray(info[0][0]) part but not sure exactly what.

UPDATE:

If there is no Post then info becomes just this:

const info = [ [ ] ]

Thats why I need to check whether info[0][0] is empty or not

Answer 1

I believe you have a bug when you call Array.isArray . You gave the input info[0][0] , but you want to check if Array[0] is an array.

New code with fixed bug:

const info = [
    [
        {
            "Post": 7
        }
    ]
]

let Result;
     if (!Array.isArray(info[0]) || info[0].length === 0) {
        Result = {"Error": "No info"}
     }

Edit: Also removed extra [0] when checking length.

Answer 2

Array.isArray returns false because info[0][0] is { "Post": 7 }