Question

我从另一个StackOverflow 邮报复制了这个代码。但是, 我对它有些问题。符合指定模式的物品应该替换, 但是没有替换。

代码是:

protected String FixHexValuesInString(String str){
    Log.v(TAG, "before fix: "+ str);
    Matcher matcher = Pattern.compile("\\x([0-9a-f]{2})").matcher(str);
    while (matcher.find()) {
        int codepoint = Integer.valueOf(matcher.group(1), 16);
        Log.v(TAG, "matcher group 0: " + matcher.group(0));
        Log.v(TAG, "matcher group 1: " + matcher.group(1));
        str = str.replaceAll(matcher.group(0), String.valueOf((char) codepoint));
    }
    Log.v(TAG, " after fix: "+ str);
    return str;
}

我给LogCat写了个例子:

before fix:  id : 1268,  name :  Reserva de Usos Mxfaltiples de la Cuenca del Lago de Atitlxe1n-RUMCLA (Atitlxe1n Watershed Multiple Use Reserve) 
matcher group 0: xfa
matcher group 1: fa
matcher group 0: xe1
matcher group 1: e1
matcher group 0: xe1
matcher group 1: e1
 after fix:  id : 1268,  name :  Reserva de Usos Mxfaltiples de la Cuenca del Lago de Atitlxe1n-RUMCLA (Atitlxe1n Watershed Multiple Use Reserve)

有人知道为什么这行不通吗?

Answer 1

当您在进行常规表达式匹配和替换时, 根本不应该使用 String. replaceall 方法... 您应该使用在 < a href=" http://docs. oracle.com/javase/6/docs/ api/java/ va/ util/ regex/ Matcher. html# append replace% 28java. lang. StringBuffer,% 20java. lang. string% 29" rel="no folpol"\\ code>Matser. append Replation 和 < a href=" http://docs. oracle.com/javase/6/ javatile/regex/ Matcher. html# appendendTail% 28java. l. l. tringBuffer% 29" rel=" nofol"\\colcode@ dock> Matcher. appendtail 方法如下:

public static void main(String[] args) {

    String str = " id : 1268,  name :  Reserva de Usos M\xfaltiples de " +
                 "la Cuenca del Lago de Atitl\xe1n-RUMCLA (Atitl\xe1n " +
                 "Watershed Multiple Use Reserve) ";

    Matcher matcher = Pattern.compile("\\x([0-9a-f]{2})").matcher(str);

    StringBuffer sb = new StringBuffer();
    while (matcher.find()) {
        int codepoint = Integer.valueOf(matcher.group(1), 16);
        matcher.appendReplacement(sb, String.valueOf((char) codepoint));
    }
    matcher.appendTail(sb);

    System.out.println(sb);
}

产出:

 id : 1268,  name :  Reserva de Usos Múltiples de la Cuenca del Lago de Atitlán-RUMCLA (Atitlán Watershed Multiple Use Reserve)

Answer 2

replaceAll () 使用第一个参数作为regex。在您的第一组中, 您有 xfa , 这是未逃脱的。请尝试在组的开头添加一个。

友情链接