Question

I am attempting to split a string of integers into an array in JavaScript.

Originally I had:

m.rows[7] = new Array   (8,11); 

And I am changing it to:

var nearby = nearby.split(",");
m.rows[7] = new Array   (nearby);

(And setting a variable with the appropriate integers separated by a comma in my level editor. When I print “nearby[0]” to the console I get ‘8’. When I print “nearby[1]” to the console I get 11)

However, I then have this code in which I attempt to match one of the elements in the array with an element in another array:

    for (var i = m.rows[id].length-1; i >= 0; i--) {
        // If the loop finds an element ID that matches the ID of the last element in the path array, do this:
        console.log('test nearby 2: ' + m.rows[id][i]);
        if (m.rows[id][i] == this.path_array[this.path_array.length-1].id) {
            // Loop through the one array 
            for (var j = all_nodes.length-1; j >= 0; j--){
                // If the ID of one of one of these entities matches the id of the instance that was just clicked
                if (all_nodes[j].id == id) {

                    // Activate that node:
                    all_nodes[j].active = true;
                }
            }
            break;
        }

When I actually put “8,11” into the array above manually the above works perfectly. However when I attempt to use “nearby” which I split into the array, it does not. And printing it to the console in “test nearby 2” above, when I use “nearby” “8,11” gets printed. When I manually enter “8,11” into that array I get “11”.

I’m fairly new to JavaScript so I’m probably missing something extremely obvious here – can anyone shed some light?

Thanks!

Answer 1

That’s not how arrays work. In new Array(8, 11), 8 and 11 are parameters. In new Array(nearby), nearby is one parameter. To achieve the functionality you need, however, it’s quite simple; nearby is already an array, so just assign it:

m.rows[7] = nearby;

Or, if the type bothers you:

m.rows[7] = [parseInt(nearby[0], 10), parseInt(nearby[1], 10)];

Note that here I used the array literal syntax, []. [a, b] is basically equivalent to new Array(a, b), and you should use the literal syntax when possible for various reasons.