Question

I tried this:

var count;

function testCount ()
{
  if (count)
  {
    alert("count is: " + count);
    count++;
  }    
  else
  {    
    alert("count is: " + count);
    var count = 0;
  }
};

testCount();

but it always gives “undefined” and the value of count is not updated when I run it again in jsfiddle.

Answer 1

It appears that nobody has shown the simple testCount() implementation. Just initialize it upon declaration and then just use it in your function:

var count = 0;

function testCount ()
{
    alert("count is: " + count);
    count++;
}

testCount();