String :: lengthInUnits - Gets the number of text elements in the current String object.
According to the coding type of the String object, the functions returns the number of base characters (all 8 bit coding types), of unsigned integers ( UTF16 ) or unsigned long ( UTF32 ). For coding type UTF8 the number of units may differ from the number of code points contained in the String object.
Return value: Maximum size of buffer or string ( int32 )