How to sort an array of strings having string length but empty string value

Quote:

How to sort an array like this ? I am getting array of strings with length but some of them are empty in markup. I need to avoid them.

[0]=> string(6) " " 
[1]=> string(5) " " 
[2]=> string(1) " " 
[3]=> string(11) "The problem"

if(array_element[0] !== ''){
  //first element is not empty
}