Create array based on variable value with javascript

Question

I have a variable with a dynamic value (from 1 to 15). Depending on the value of the variable, I want to create an array with the same length.

And, if for example the variable value is 1, I want to store A in the array, if the value is 6 I want to store A,B,C,D,E,F in the array and so on.

How do I achieve this? Thanks in advance.

• Oded: Is this homework? If so, please tag it as such.
• Anders: @Oded, Homework, in the middle of the summer?
• Oded: @Anders - It is not summer in the south of our little globe, and not everyone in the world has summer vacation right now. Global community and all, you know?
• peter: Well, I am in Australia and it's winter here. No, it's not homework, thanks.
• Anurag: wait, people outside the US have internet? woah!

Answer 1

var sizeOfArray = 6;
"ABCDEFGHIJKLMNO".slice(0, sizeOfArray).split('');
// ["A", "B", "C", "D", "E", "F"]

• peter: Thanks Anurag, so where do I create the array?
• Anurag: The second statement returns an array. The split function is doing that for you.
• bezmax: Well, he only mentioned an idea, not the full solution (nice idea btw). The full solution would be: var sizeOfArray=6; var newArray = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".slice(0, sizeOfArray).split('');
• peter: so the name of the array will be sizeOfArray?
• bezmax: No, my comment creates a variable "newArray". Original post has no variable with array. There are no line-breaks in comments so I had to put it in 1 line.

Answer 2

var arrSize = 4;
var myArray = new Array(arrSize);

or you can declare the array without size and then push a new element in it:

var myArray = new Array();
myArray.push(ITEM);

where ITEM is replaced by a variable or string or number you want to add in the array (will be added at the end of the array)

Answer 3

My 2 cents. (this function takes size> 26 into account)

<script type="text/javascript">
 function buildAlphabetArray(size) {
 var range = 26;
 var arr = new Array();
 for (var i = 0; i <= parseInt(size); i++) {
 //calculate current index (recalc to number between 0 and range)
 var j = (i < (range-1) ? i : (i - range * parseInt(i / range))); 
 //get the char value of ascii 65 + index (charAt(65)==A)
 arr[i] = String.fromCharCode(j + 65); //
 }
 //test
 //alert(arr.join(""));
 return arr;
 }
</script>

Answer 4

var a = 5;
var arr = new Array(a);
for (var i = 0;i<a;i++) {
 arr[i] = String.fromCharCode(65+i);
 document.write("arr["+i+"] = '"+arr[i]+"'<br/>");
}