I am writing a java program in which a user enters a series of words that changes every ‘p’ to a ‘b’ in the sentence (case insensitive) and displays the output.
I try to use replace function but it is not case insensitive
String result = s.replace('p', 'b');
I expect the output boliticians bromised, but the actual outputs is Politicians bromised.
replace is case sensitive only.
There is no "simple" way to do this: you could do two replacements, but that constructs an intermediate string.
String result = s.replace('p', 'b').replace('P', 'B');
I would do this by iterating the character array:
char[] cs = s.toCharArray();
for (int i = 0; i < cs.length; ++i) {
switch (cs[i]) {
case 'p': cs[i] = 'b'; break;
case 'P': cs[i] = 'B'; break;
}
}
String result = new String(cs);
If you wanted to write a method to do this for non-hardcoded letters, you could do it like:
String method(String s, char from, char to) {
char ucFrom = Character.toUpperCase(from); // Careful with locale.
char ucTo = Character.toUpperCase(to);
char[] cs = s.toCharArray();
for (int i = 0; i < cs.length; ++i) {
if (cs[i] == from) { cs[i] = to; }
else if (cs[i] == ucFrom) { cs[i] = ucTo; }
}
return new String(cs);
}
You can do it using regex, see Q&A - How to replace case-insensitive literal substrings in Java or you can use replace twice for p and P
You can use replaceAll instead so you can use a regular expression:
String result = s.replaceAll("[pP]", "b");
