[javascript] Javascript dynamic array of strings

Is there a way to create a dynamic array of strings on Javascript? What I mean is, on a page the user can enter one number or thirty numbers, then he/she presses the OK button and the next page shows the array in the same order as it was entered, one element at a time.

Code is appreciated.

This question is related to javascript arrays

The answer is


var junk=new Array();
junk.push('This is a string.');

Et cetera.


As far as I know, Javascript has dynamic arrays. You can add,delete and modify the elements on the fly.

var myArray = [1,2,3,4,5,6,7,8,9,10];
myArray.push(11);
document.writeln(myArray);  // Gives 1,2,3,4,5,6,7,8,9,10,11


var myArray = [1,2,3,4,5,6,7,8,9,10];
var popped = myArray.pop();
document.writeln(myArray);  // Gives 1,2,3,4,5,6,7,8,9

You can even add elements like

var myArray = new Array()
myArray[0] = 10
myArray[1] = 20
myArray[2] = 30

you can even change the values

myArray[2] = 40

Printing Order

If you want in the same order, this would suffice. Javascript prints the values in the order of key values. If you have inserted values in the array in monotonically increasing key values, then they will be printed in the same way unless you want to change the order.

Page Submission

If you are using JavaScript you don't even need to submit the values to the different page. You can even show the data on the same page by manipulating the DOM.


Just initialize an array and push the element on the array. It will automatic scale the array.

var a = [ ];

a.push('Some string'); console.log(a); // ['Some string'] 
a.push('another string'); console.log(a); // ['Some string', 'another string'] 
a.push('Some string'); console.log(a); // ['Some string', 'another string', 'Some string']

Here is an example. You enter a number (or whatever) in the textbox and press "add" to put it in the array. Then you press "show" to show the array items as elements.

<script type="text/javascript">

var arr = [];

function add() {
   var inp = document.getElementById('num');
   arr.push(inp.value);
   inp.value = '';
}

function show() {
   var html = '';
   for (var i=0; i<arr.length; i++) {
      html += '<div>' + arr[i] + '</div>';
   }
   var con = document.getElementById('container');
   con.innerHTML = html;
}

</script>

<input type="text" id="num" />
<input type="button" onclick="add();" value="add" />
<br />
<input type="button" onclick="show();" value="show" />
<div id="container"></div>

Please check http://jsfiddle.net/GEBrW/ for live test.

You can use similar method for dynamic arrays creation.

var i = 0;
var a = new Array();

a[i++] = i;
a[i++] = i;
a[i++] = i;
a[i++] = i;
a[i++] = i;
a[i++] = i;
a[i++] = i;
a[i++] = i;

The result:

a[0] = 1
a[1] = 2
a[2] = 3
a[3] = 4
a[4] = 5
a[5] = 6
a[6] = 7
a[7] = 8

You can go with inserting data push, this is going to be doing in order

var arr = Array();
function arrAdd(value){
    arr.push(value);
}

The following code creates an Array object called myCars:

var myCars=new Array();

There are two ways of adding values to an array (you can add as many values as you need to define as many variables you require).

1:

var myCars=new Array();
myCars[0]="Saab";
myCars[1]="Volvo";
myCars[2]="BMW";

You could also pass an integer argument to control the array's size:

var myCars=new Array(3);
myCars[0]="Saab";
myCars[1]="Volvo";
myCars[2]="BMW";

2:

var myCars=new Array("Saab","Volvo","BMW");

Note: If you specify numbers or true/false values inside the array then the type of variables will be numeric or Boolean instead of string.

Access an Array

You can refer to a particular element in an array by referring to the name of the array and the index number. The index number starts at 0.

The following code line:

document.write(myCars[0]);

will result in the following output:

Saab

Modify Values in an Array

To modify a value in an existing array, just add a new value to the array with a specified index number:

myCars[0]="Opel";

Now, the following code line:

document.write(myCars[0]);

will result in the following output:

Opel