I've reading this question, and I was wondering if Is there any way to consider the whole range of characters? For example, "á", "é", "ö", "ñ", and not consider " " (the [Space])? (For example, my String is "Hello World", and the standard result is "Khoor#Zruog"; I want to erase that "#", so the result would be "KhoorZruog")
I'm sure my answer is in this piece of code:
if (c >= 32 && c <= 127)
{
// Change base 开发者_如何学JAVAto make life easier, and use an
// int explicitly to avoid worrying... cast later
int x = c - 32;
x = (x + shift) % 96;
chars[i] = (char) (x + 32);
}
But I've tried some things, and it didn't work.
See this pseudocode - should be trivially implementable:
// you need to define your own range, obviously - it's not at all obvious whether
// e.g. "ź" should be included and that it should come after "z"
array char_range = ['a','á','b','c','č', (...), 'z','ź','ž']
// the text to encode
string plaintext = 'some text here'
// this will contain encoded text
stringbuilder ciphertext = ''
// the classic Caesar Cipher shifts by 3 chars to the right
// to decipher, reverse the sign
int shift_by = 3
// note: character != byte, esp. not in UTF-8 (1 char could be 1 or more bytes)
for each character in plaintext
get character_position of character in char_range // e.g. "a" would return 0
if not in char_range // e.g. spaces and other non-letters
do nothing // drop character
// alternately, you can append it to ciphertext unmodified
continue with next character
add shift_by to character_position
if character_position > char_range.length
character_position modulo char_range.length
if character_position < 0 // useful for decoding
add char_range.length to character_position
get new_character at character_position
append new_character to ciphertext
done
The Space as the ASCII Code 32 which you don't filter out. You could try:
if (c >= 33 && c <= 127)
{
// Change base to make life easier, and use an
// int explicitly to avoid worrying... cast later
int x = c - 32;
x = (x + shift) % 96;
chars[i] = (char) (x + 32);
}
I just changed the 32 with a 33 in your if-Clause so that the spaces are simply ignored.
You could use this. It will check for you it the given int value represents a literal. Character
So your function could look like this:
if (Character.isLiteral(c) )
{
// Change base to make life easier, and use an
// int explicitly to avoid worrying... cast later
int x = c - Character.MIN_VALUE;
x = (x + shift) % Character.MAX_VALUE;
chars[i] = (char) (x + Character.MIN_VALUE);
}
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