I want to generate a string of random letters say 10 letters from a-z one after the other i.e. the next letter should be displayed after the previous letter after a certain delay, later, I want to calculate the number of times each letter has been generated, unlike what I have done previously, i.e. I have taken a predefined array of letters and generated them accordingly.

I want to generate a string of random letters say 10 letters from a-z one after the other i.e. the next letter should be displayed after the previous letter after a certain delay, later, I want to calculate the number of times each letter has been generated, unlike what I have done previously, i.e. I have taken a predefined array of letters and generated them accordingly.

• javascript
• html

• possible duplicate of Generate a string of 5 random characters in Javascript – Phrogz Commented Apr 20, 2013 at 17:49
• When should it count number of occurrences? Where should those numbers be printed. Clarify your question. – dfsq Commented Apr 20, 2013 at 17:55
• As soon as the string is generated , the no of occurrences may be counted, and they could be displayed in a text box or a text area... – user2301239 Commented Apr 20, 2013 at 18:02

3 Answers 3

Shorter way to generate such a string using String.fromCharCode:

for (var i = 0, letter; i < 10; i++) {
    setTimeout(function() {
        letter = String.fromCharCode(97 + Math.floor(Math.random() * 26));
        out.appendChild(document.createTextNode(letter)); // append somewhere
    }, 2000 * i);
}

And plete demo covering all the problems in this question: http://jsfiddle/p8Pjq/

Use the setInterval method to run code at an interval. Set up an array for counting each character from the start, then you can count them when you create them instead of afterwards:

var text = '';
var chars = 'abcdefghijklmnopqrstuvwxyz';
var cnt = new Array(chars.length);
for (var i = 0; i < cnt.length; i++) cnt[i] = 0;

var handle = window.setInterval(function(){
    var ch = Math.floor(Math.random() * chars.length);
    cnt[ch]++;
    text += chars.charAt(ch);
    $('#display').text(text);
    if (text.length == 20) {
      window.clearInterval(handle);
      // now all characrers are created and counted
    }
}, 2000);

Demo: http://jsfiddle/R8rDH/

I am stealing this answer, but look here: Generate random string/characters in JavaScript

function makeid()
{
    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

    for( var i=0; i < 5; i++ )
        text += possible.charAt(Math.floor(Math.random() * possible.length));

    return text;
}