使用split(“|”)将Java字符串分割为管道符号

The Java official documentation states:

Java官方文件说明:

The string "boo:and:foo", for example, yields the following results with these expressions Regex Result :

例如，字符串“boo:and:foo”通过以下表达式Regex结果生成以下结果:

{ "boo", "and", "foo" }"

And that's the way I need it to work. However, if I run this:

这就是我需要它工作的方式。但是，如果我运行这个:

public static void main(String[] args){
        String test = "A|B|C||D";

        String[] result = test.split("|");

        for(String s : result){
            System.out.println(">"+s+"<");
        }
    }

it prints:

它打印:

><
>A<
>|<
>B<
>|<
>C<
>|<
>|<
>D<

Which is far from what I would expect:

这远不是我所期望的:

>A<
>B<
>C<
><
>D<

Why is this happening?

为什么会这样?

6 个解决方案

#1

342

You need

你需要

test.split("\\|");

split uses regular expression and in regex | is a metacharacter representing the OR operator. You need to escape that character using \ (written in String as "\\" since \ is also a metacharacter in String literals and require another \ to escape it).

split使用正则表达式，在regex |中是表示OR操作符的元字符。您需要使用\(以字符串形式写成“\”，因为\也是字符串形式的元字符，需要另一个\来转义它)来转义该字符。

You can also use

您还可以使用

test.split(Pattern.quote("|"));

and let Pattern.quote create the escaped version of the regex representing |.

我们的模式。引用创建代表|的正则表达式的转义版本。

#2

Use proper escaping: string.split("\\|")

使用正确的转义:string.split(“\ \ |”)

Or the helper Pattern.quote() which has been created for exactly this purpose:

或者是帮助模式。quote()就是为了这个目的而创建的:

string.split(Pattern.quote("|"))

which works with arbitrary input strings. Very useful when you need to quote / escape user input.

它适用于任意输入字符串。当您需要引用/转义用户输入时非常有用。

#3

Use this code:

使用这段代码:

public static void main(String[] args) {
    String test = "A|B|C||D";

    String[] result = test.split("\\|");

    for (String s : result) {
        System.out.println(">" + s + "<");
    }
}

#4

You could also use the apache library and do this:

您还可以使用apache库并完成以下操作:

StringUtils.split(test, "|");

#5

You can also use .split("[|]").

您也可以使用.split(“[|]”)。

(I used this instead of .split("\\|"), which didn't work for me.)

(我用这个代替了。split(“\|”)，它对我不起作用。)

#6

-1

the split() method takes a regular expression as an argument

split()方法以正则表达式作为参数。

#1

342