removing space before new line in java

问题

i have a space before a new line in a string and cant remove it (in java). I have tried the following but nothing works:

strToFix = strToFix.trim();
strToFix = strToFix.replace(" \n", "");
strToFix = strToFix.replaceAll("\\s\\n", "");

回答1:

myString.replaceAll("[ \t]+(\r\n?|\n)", "$1");

replaceAll takes a regular expression as an argument. The [ \t] matches one or more spaces or tabs. The (\r\n?|\n) matches a newline and puts the result in $1.

回答2:

try this:

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

'\' is a special character in regex, you need to escape it use '\'.

回答3:

I believe with this one you should try this instead:

strToFix = strToFix.replace(" \\n", "\n");

Edit:

I forgot the escape in my original answer. James.Xu in his answer reminded me.

回答4:

Are you sure?

String s1 = "hi     ";
System.out.println("|" + s1.trim() + "|");

String s2 = "hi     \n";
System.out.println("|" + s2.trim() + "|");

prints

|hi|
|hi|

回答5:

are you sure it is a space what you're trying to remove? You should print string bytes and see if the first byte's value is actually a 32 (decimal) or 20 (hexadecimal).

回答6:

trim() seems to do what your asking on my system. Here's the code I used, maybe you want to try it on your system:

public class so5488527 {
    public static void main(String [] args)
    {
        String testString1 = "abc \n";
        String testString2 = "def \n";
        String testString3 = "ghi \n";
        String testString4 = "jkl \n";
        testString3 = testString3.trim();
        System.out.println(testString1);
        System.out.println(testString2.trim());
        System.out.println(testString3);
        System.out.println(testString4.trim());
    }
}

来源：https://stackoverflow.com/questions/5488527/removing-space-before-new-line-in-java

标签

java

newline