I have an array with som arrays ...
Now I want to check if an array already exists in the array... is that posible?..
arr1 = [0, 0];
arr2 = [[0, 0], [0, 1]]
console.log($.inArray(arr1, arr2));
return : -1
4 Answers
inArray won't do because they're two different objects even if they contain the same values so:
console.log([0,0] == [0,0]); //=> false, they're different objects
You'd have to loop and check if the values match:
var has = false;
for (var i=0; i<arr2.length; i++) {
if (arr2[i][0] === arr1[0] && arr2[i][1] === arr1[1]) {
has = true;
break;
}
}
Comments
Of course it's possible. Only question is what approach you want to take.
Here's an approach that handles more complex arrays.
function arrayInArray(arr, arrs) {
return arrs.some(function (curr) {
return curr.length === arr.length &&
curr.every(function (_, i) {
return curr[i] === arr[i]
})
})
}
This makes sure there's an equal number of items in the matching Array, and that the items appear in the same order as the original.
DEMO: http://jsfiddle.net/KEKcX/
console.log(arrayInArray([0,0], arr2)); // true
console.log(arrayInArray([0,1], arr2)); // true
console.log(arrayInArray([1,0], arr2)); // false
Comments
Here's a generic function that will loop trough the arrays.
function arrayContains(big, small) {
for (var i = 0; i < big.length; i++) {
if (big[i].length === small.length) {
var j = 0;
while (j < small.length && small[j] === big[i][j]) j++;
if (j === small.length) return true;
}
}
return false;
}
Usage:
arr1 = [0, 0];
arr2 = [[0, 0], [0, 1]];
console.log(arrayContains(arr2, arr1)); // true
console.log(arrayContains(arr2, [0, 1])); // true
console.log(arrayContains(arr2, [0, 0, 0])); // false
console.log(arrayContains(arr2, [1, 0])); // false
console.log(arrayContains(arr2, [1, 1])); // false
Comments
What about using JSON.stringify when doing comparison?
function contains (obj1, obj2) {
for (key in obj1)
if (JSON.stringify(obj1[key]) == JSON.stringify(obj2))
return true;
return false;
}
contains([[0,1], [0,0,1]], [0,1]) // => true
contains({foo: [0,1], bar: [0,0,1]}, [0,1]) // => true
[0,0] != [0,0]. So you'd have to loop and compare.