从Java字符串中去除前导和尾随空格

Question

是否有一种方便的方法可以从Java字符串中剥离任何前导或尾随空格？就像是：String myString = "  keep this  ";String stripppedString = myString.strip();System.out.println("no spaces:" + strippedString);结果：no spaces:keep thismyString.replace(" ","") 将替换keep和this之间的空间。

Answer 1

您可以尝试trim（）方法。

String newString = oldString.trim();

看看javadocs

Answer 2

trim（）是您的选择，但是如果您想使用replacemethod －可能更灵活，则可以尝试以下操作：

String stripppedString = myString.replaceAll("(^ )|( $)", "");

Answer 3

现在，使用java-11，您可以利用String.stripAPI返回一个值为该字符串的字符串，并删除所有前导和尾随空格。相同的javadoc读取：

/**

 * Returns a string whose value is this string, with all leading

 * and trailing {@link Character#isWhitespace(int) white space}

 * removed.

 * <p>

 * If this {@code String} object represents an empty string,

 * or if all code points in this string are

 * {@link Character#isWhitespace(int) white space}, then an empty string

 * is returned.

 * <p>

 * Otherwise, returns a substring of this string beginning with the first

 * code point that is not a {@link Character#isWhitespace(int) white space}

 * up to and including the last code point that is not a

 * {@link Character#isWhitespace(int) white space}.

 * <p>

 * This method may be used to strip

 * {@link Character#isWhitespace(int) white space} from

 * the beginning and end of a string.

 *

 * @return  a string whose value is this string, with all leading

 *          and trailing white space removed

 *

 * @see Character#isWhitespace(int)

 *

 * @since 11

 */

public String strip()

这些示例案例可能是：-

System.out.println("  leading".strip()); // prints "leading"

System.out.println("trailing  ".strip()); // prints "trailing"

System.out.println("  keep this  ".strip()); // prints "keep this"