Extracting the number at the end of a variable name

I am passing the name of a variable into a javascript function onmouseover event. The variable being passed in starts with letters and ends with numbers, and I want to extract the numbers from the variable name. How can I do that?

Example code:

Lets say we pass in x = abc123

function(x){
    extractednumber = parseInt(x.substring(2))
    document.write(extractednumber);
}

EDIT: The variable name has 3 characters in fro开发者_开发问答nt and a unknown number of digits behind.

a simple regexp pattern :

x.match(/([0-9]*)$/)[0]

then you could write :

function(x){
    extractednumber = parseInt(x.match(/([0-9]*)$/)[0]);
    document.write(extractednumber);
}

function GetNumber(num)
{
  var numberPart = num.replace (/[^\d]/g, “”); //use only digits
  var extractednumber = parseInt(numberPart, 10);
  return extractednumber;
}

Use regular expressions to parse the string:

if (/(\d+)$/.test(x))
  extractedNumber = parseInt(RegExp.$1, 10);

If you always have exactly three characters in front, and then an unknown number of digits afterward, you can just use substr.

function(inputString) {
    return inputString.substr(3, inputString.length);
}