I want to search an array of arrays and see if there exists an array equal to a certain array I supply. I tried to use indexOf() but that wouldn't work. Does anyone have a good technique for this?
var ary = [['1','2'],['3','4'],['5','6']];
ary.indexOf(['1','2']); //I want to get 0 here, or something like -1 if it's not present
var ary = [['1','2'],['3','4'],['5','6']];
function contains( array, value ){
for ( var i = 0; i < array.length; i++ ){
if ( array[i] === value )
return true;
if ( value instanceof Array
&& array[i] instanceof Array
&& value.length == array[i].length ){
var found = true;
for ( var j = 0; j < value.length; j++ )
if ( value[j] !== array[i][j] )
found = false;
if ( found )
return true;
}
}
return false;
}
console.log( contains( ary, ['1','2'] ) );
console.log( contains( ary, [1,'2'] ) );
console.log( contains( ary, ['3','4'] ) );Use indexOf with join. It's not necessary with one dimensional arrays, but is a valid approach in this escenario:
var comp = ['1','2'];
for(var i = 0, j = ary.length;i < j;i++) {
if(ary[i].join().indexOf(comp.join()) >= 0) {
//do stuff here
}
}
ary[i].join() === comp.join() would make it a lot clearer what you are doing here.What you are doing can actually yield false positives. Consider [1, [1,2]] vs [1,2].
As for my knowledge, JavaScript has no function to check the index of a multidimensional array. You could do that manually: you declare the two values you want to find, then loop thorugh the array and check if the first and the second element of the current subarray match your condition... ... OK, I think an example is needed, sorry for my horrible explanation!
function indexMultiDArray (myArr){
var check = ['n1','n2'];
var i=0;
for (i; i < myArr.length; i++){
if (myArr[i][0]===check[0] && myArr[i][1]===check[1]){
alert(myArr[i][0]+' '+myArr[i][1]);
}
}
}
Basically, you loop through it: if the first and the second element of the current couplet match the first and the second element of the check couplet, you have it: do something with it ;)
