查找數組是否在二維數組中

Question

我想知道數組是否在二維數組內。

這是我的嘗試：

var x=[1,2]; 
var y=[[1,1],[1,2],[2,2],[3,3]]; 

y.includes(x); //should return true 

Answer 1

你可以用鏈式陣列的方法做到這一點！

var ar = [ 
    [1,1],[1,2],[2,2],[3,3] 
]; 

hasDuplicates(ar, [1,"1"]); //false 
hasDuplicates(ar, [1,1]); //true 

//Use some to determine at least 1 inner array matches 
function hasDuplicates(array, valueToCheck) { 
    return array.some(function(a, i) { 
     //Check each inner arrays index, and verify that it equals on the same index of the array we want to check 
     return a.every(function(ax, ix) { 
      return valueToCheck[ix] === ax; //triple equals for equality! 
     }) 
    }); 
} 

演示：https://jsfiddle.net/a3rq70hL/1/

Answer 2

你可以創建一個哈希：

var ar = [ 
 
    [1,1],[1,2],[2,2],[3,3] 
 
]; 
 

 
var hash = {}; 
 
for(var i = 0 ; i < ar.length; i += 1) { 
 
    hash[ar[i]] = i; 
 
} 
 

 
var val = [1,2]; 
 

 
if(hash.hasOwnProperty(val)) { 
 
    document.write(hash[val]); 
 
}