Predefined Constants
 
The constants below are defined by this extension, and
will only be available when the extension has either
been compiled into PHP or dynamically loaded at runtime.
 
  
   - 
    MB_OVERLOAD_MAIL(int)
- 
    
     Removed as of PHP 8.0.0.
    
   
- 
    MB_OVERLOAD_STRING(int)
- 
    
     Removed as of PHP 8.0.0.
    
   
- 
    MB_OVERLOAD_REGEX(int)
- 
    
     Removed as of PHP 8.0.0.
    
   
- 
    MB_CASE_UPPER(int)
- 
    
     Performs a full upper-case folding.
     This may change the length of the string.
     This is the mode used by mb_strtoupper().
    
   
- 
    MB_CASE_LOWER(int)
- 
    
     Performs a full lower-case folding.
     This may change the length of the string.
     This is the mode used by mb_strtolower().
    
   
- 
    MB_CASE_TITLE(int)
- 
    
     Performs a full title-case conversion based on the Cased and CaseIgnorable
     derived Unicode properties.
     In particular this improves handling of quotes and apostrophes.
     This may change the length of the string.
    
   
- 
    MB_CASE_FOLD(int)
- 
    
     Performs a full case fold conversion which removes case distinctions
     present in the string.
     This is used for caseless matching.
     This may change the length of the string.
     Available since PHP 7.3.
    
   
- 
    MB_CASE_LOWER_SIMPLE(int)
- 
    
     Performs a simple lower-case fold conversion.
     This does not change the length of the string.
     Available as of PHP 7.3.
    
   
- 
    MB_CASE_UPPER_SIMPLE(int)
- 
    
     Performs simple upper-case fold conversion.
     This does not change the length of the string.
     Available as of PHP 7.3.
    
   
- 
    MB_CASE_TITLE_SIMPLE(int)
- 
    
     Performs simple title-case fold conversion.
     This does not change the length of the string.
     Available as of PHP 7.3.
    
   
- 
    MB_CASE_FOLD_SIMPLE(int)
- 
    
     Performs a simple case fold conversion which removes case distinctions
     present in the string.
     This is used for caseless matching.
     This does not change the length of the string.
     Used by case-insensitive operations internally by the MBString extension.
     Available as of PHP 7.3.
    
   
- 
    MB_ONIGURUMA_VERSION(string)
- 
    
     The Oniguruma version, e.g. 6.9.4.
     Available as of PHP 7.4.