Java替换字符串中的特殊字符

Question

I have a string like this:

BEGIN\n\n\n\nTHIS IS A STRING\n\nEND

And I want to remove all the new line characters and have the result as :

BEGIN THIS IS A STRING END

How do i accomplish this? The standard API functions will not work because of the escape sequence in my experience.

Answer 1

Try str.replaceAll("\\\\\\\\n", ""); - this is called double escaping :)

Answer 2

A simple replace('\\n', ' ') will cause the string to become:

 BEGIN    THIS IS A STRING  END
      ****                **

where the * 's are spaces. If you want single spaces, try replaceAll("[\\r\\n]{2,}", " ")

And in case they're no line breaks but literal "\\n" 's wither try:

replace("\\n", " ")

or:

replaceAll("(\\\\n){2,}", " ")

Answer 3

String str = "BEGIN\n\n\n\nTHIS IS A STRING\n\nEND;";

str = str.replaceAll("\\\n", " ");

// Remove extra white spaces
while (str.indexOf("  ") > 0) {
   str = str.replaceAll("  ", " ");
}

Answer 4

This works for me:

String s = "BEGIN\n\n\n\nTHIS IS A STRING\n\nEND";
String t = s.replaceAll("[\n]+", " ");
System.out.println(t);

The key is the reg-ex.

Answer 5

当然，标准API可以使用，但是您可能必须进行两次转义（“ \\\\ n”）。

Answer 6

I don't usually code in Java, but a quick search leads me to believe that String.trim should work for you. It says that it removes leading and trailing white space along with \\n \\t etc...

Answer 7

Hope this snippet will help,

Scanner sc = new Scanner(new StringReader("BEGIN\n\n\n\nTHIS IS A STRING\n\nEND "));
    String out = "";
    while (sc.hasNext()) {
        out += sc.next() + " ";
    }
    System.out.println(out);