How to replace special characters in a string?

Question

I have a string with a lot of special characters. I want to remove all of these, but keep the alphabetic characters.

How can i do this?

Answer 1

It depends on what you mean. If you just want to get rid of them, do the following:
(Update: apparently you also want to keep the numbers, use the second line in this case)

String alphaOnly = input.replaceAll("[^a-zA-Z]+",""); String alphaAndDigits = input.replaceAll("[^a-zA-Z0-9]+",""); 

or equivalent:

 String alphaOnly = input.replaceAll("[^\\p{Alpha}]+",""); String alphaAndDigits = input.replaceAll("[^\\p{Alpha}\\p{Digit}]+",""); 

(All of this can be greatly improved by precompiling the regex pattern and storing it in a constant)

Or, Guava :

 private static final CharMatcher ALNUM = CharMatcher.inRange('a', 'z').or(CharMatcher.inRange('A', 'Z')) .or(CharMatcher.inRange('0', '9')).precomputed(); // ... String alphaAndDigits = ALNUM.retainFrom(input); 

But if you want to turn accented characters into something reasonable that is still ascii, look at these questions:

• Convert Java string to ASCII
• Java change in aeouu
• ń ǹ ň ň ṅ ņ ṇ ṋ ṉ ̈ ɲ ƞ ᶇ ɳ ȵ → n or Remove diacritics from Unicode characters

Answer 2

I am using this.

 s = s.replaceAll("\\W", ""); 

It replaces all special characters from the string.

Here

\ w: word character abbreviated for [a-zA-Z_0-9]

\ W: character without a word

Answer 3

You can use the following method to store alphanumeric characters.

 replaceAll("[^a-zA-Z0-9]", ""); 

And if you want to keep only alphabetic characters, use this

 replaceAll("[^a-zA-Z]", ""); 

Answer 4

 string Output = Regex.Replace(Input, @"([ a-zA-Z0-9&, _]|^\s)", ""); 

Here all special characters except space, comma and ampersand are replaced. You can also omit the space, comma, and ampersand with the following regular expression.

 string Output = Regex.Replace(Input, @"([ a-zA-Z0-9_]|^\s)", ""); 

Where Input is the string we need to replace the characters.

Answer 5

Replace any special characters with

 replaceAll("\\your special character","new character"); 

for example: replace all occurrences * with a space

 replaceAll("\\*",""); 

* this statement can replace only one type of special character at a time

Answer 6

Following the example of Andrzej Doyle's answer , I think the best solution would be to use org.apache.commons.lang3.StringUtils.stripAccents() :

 package bla.bla.utility; import org.apache.commons.lang3.StringUtils; public class UriUtility { public static String normalizeUri(String s) { String r = StringUtils.stripAccents(s); r = r.replace(" ", "_"); r = r.replaceAll("[^\\.A-Za-z0-9_]", ""); return r; } } 

Answer 7

You can use basic regular expressions for strings to find all special characters, or use pattern classes and classes to find / modify / delete user-defined strings. This link contains some simple and straightforward examples for regular expressions: http://www.vogella.de/articles/JavaRegularExpressions/article.html

Answer 8

You can get the unicode for this garbage symbol from the charactermap tool in the pc window and add \ u e.g.. \ U00a9 for the copyright symbol. Now you can use this line with this particular junk caharacter, not delete the junk email character, but replace it with the corresponding unicode.

Answer 9

For spaces use "[^ az AZ 0-9]" this pattern