Javascript创建多维数组

Question

I try to create a 4-dimensional array. I fill it dynamically and use content of it in another function. But the content is empty. Is there error below code?

    var datas = []; // day number of a week
    for(var i = 0; i < 7; i++) {
            var size = 24*60/timeInterval;
            datas[i] = [];

            for(var j = 0; j < size; j++) {
                var size2 = allCoords.length / 2;
                datas[i][j] = [];

                for(var k = 0; k < size2; k++) {
                    datas[i][j][k] = [];
                }
            }
        }

I test below example :

function foo1()
{
    datas[0][0][0].push(10);
}

function foo2()
 {

     document.getElementByID('result').innerHTML = datas[0][0][0];
 }

I see only ,,,,,,, .

Answer 1

I think the principal problem is that you're getting the element where you want to show your result badly using getElementByID instead of getElementById . Also make sure that your element has innerHTML property to write the result, or alternatively use value .

I write the follow example using <textArea id="result"></textArea> and generating a button which calls foo1();foo2(); onClick an it works for me.

In the sample I use an random value for timeInterval and allCoords.length .

Note also that you want a 4-dimensional array however you're creating a 3-dimensional.

 var timeInterval = 60; var allCoords = { length : 1}; var datas = []; // day number of a week for(var i = 0; i < 7; i++) { var size = 24*60/timeInterval; datas[i] = []; for(var j = 0; j < size; j++) { var size2 = allCoords.length / 2; datas[i][j] = []; for(var k = 0; k < size2; k++) { datas[i][j][k] = []; } } } function foo1() { datas[0][0][0].push(10); } function foo2() { document.getElementById('result').value = datas[0][0][0]; } 

 <textArea id="result"></textArea> <input type="button" value="foo" onclick="foo1();foo2();"/> 

Hope this helps,