遇到一个很奇怪的问题，java字符串的
本帖最后由 oACheng1 于 2014-01-09 10:21:53 编辑 我有一个字符串
比如 s = select * from abc[x][y][z]
x=de,y=fg,z=hi
现在需要替换字符串 我是用这种方法替换的,因为后面或许还有x，只替换第一个[x]
s=s.replaceFirst("["+"x"<这里是个变量，我在这先写死了>+"]",x);
问题出现了，在编码时，""是表示字符串的，中间应该变成粗体，他却是普通的字体，我以为就是个显示问题，就没有在意，写了个main方法测试时发现，"["根本就没有匹配，就是说，他没有起作用，只是替换了x而已，
而换成replace 后就一切恢复了正常，请问这是怎么回事，以前从来没有遇到过
[解决办法]
String s="sd[dsd]88bb";
System.out.println(s);
System.out.println(s.replace("[", "----"));
System.out.println(s.replaceFirst("\\[", "----"));
/**
* Replaces the first substring of this string that matches the given <a
* href="../util/regex/Pattern.html#sum">regular expression</a> with the
* given replacement.
*
* <p> An invocation of this method of the form
* <i>str</i><tt>.replaceFirst(</tt><i>regex</i><tt>,</tt> <i>repl</i><tt>)</tt>
* yields exactly the same result as the expression
*
* <blockquote><tt>
* {@link java.util.regex.Pattern}.{@link java.util.regex.Pattern#compile
* compile}(</tt><i>regex</i><tt>).{@link
* java.util.regex.Pattern#matcher(java.lang.CharSequence)
* matcher}(</tt><i>str</i><tt>).{@link java.util.regex.Matcher#replaceFirst
* replaceFirst}(</tt><i>repl</i><tt>)</tt></blockquote>
*
*<p>
* Note that backslashes (<tt>\</tt>) and dollar signs (<tt>$</tt>) in the
* replacement string may cause the results to be different than if it were
* being treated as a literal replacement string; see
* {@link java.util.regex.Matcher#replaceFirst}.
* Use {@link java.util.regex.Matcher#quoteReplacement} to suppress the special
* meaning of these characters, if desired.
*
* @param regex
* the regular expression to which this string is to be matched
* @param replacement
* the string to be substituted for the first match
*
* @return The resulting <tt>String</tt>
*
* @throws PatternSyntaxException
* if the regular expression's syntax is invalid
*
* @see java.util.regex.Pattern
*
* @since 1.4
* @spec JSR-51
*/
public String replaceFirst(String regex, String replacement) {
return Pattern.compile(regex).matcher(this).replaceFirst(replacement);
}
