str_decrement
  Decrement an alphanumeric string
  
 
  Description
  
   string str_decrement(string $string)
  
  
 
  Parameters
  
   
    
     - 
string
- 
      
       The input string.
       
 
 
  Return Values
  
   Returns the decremented alphanumeric ASCII string.
  
  
 
  Errors/Exceptions
  
   A ValueError is thrown if
   string is empty.
  
  
   A ValueError is thrown if
   string is not an alphanumeric
   ASCII string.
  
  
   A ValueError is thrown if
   string cannot be decremented.
   For example, "A" or "0".
  
  
 
  Examples
  
   
    Example #1 Basic str_decrement example
    
<?php
$str = 'ABC';
var_dump(str_decrement($str));
?>
 
    The above example will output:
 
  
  
   
    Example #2 str_decrement example with a carry
    
<?php
$str = 'ZA';
var_dump(str_decrement($str));
$str = 'AA';
var_dump(str_decrement($str));
?>
 
    The above example will output:
string(2) "YZ"
string(1) "Z"