solr系统query检索词特殊字符的处理

solr是基于 lucence开发的应用，如果query中带有非法字符串，结果很可能是检索出所有内容或者直接报错，所以你对用户的输入必须要先做处理。输入星号，能够检索出所有内容；输入加号，则会报错。

官方的处理办法（java，因为solr是java开发的）：

https: //svn.apache.org/repos/asf/lucene/dev/trunk/solr/solrj/src/java/org/apache/solr/client/solrj/util/ClientUtils.java

public static String escapeQueryChars(String s) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < s.length(); i++) {
char c = s.charAt(i);
// These characters are part of the query syntax and must be escaped
if (c == '\\' || c == '+' || c == '-' || c == '!' || c == '(' || c == ')' || c == ':'
|| c == '^' || c == '[' || c == ']' || c == '\"' || c == '{' || c == '}' || c == '~'
|| c == '*' || c == '?' || c == '|' || c == '&' || c == ';' || c == '/'
|| Character.isWhitespace(c)) {
sb.append( '\\');
}
sb.append(c);
}
return sb.toString();
}

翻译的php版本（利用preg_replace函数进行正则替换）：

static public function escape($value)
{
//list taken from http://lucene.apache.org/java/docs/queryparsersyntax.html#Escaping%20Special%20Characters
$pattern = '/(\+|-|&|\||!|\(|\)|\{|}|\[|]|\^|"|~|\*|\?|:|;|~|\/)/';
$replace = '\\\$1';

return preg_replace($pattern, $replace, $value);
}

翻译后的python版本：

C#版

    /// <summary>
    /// solr查询字符串特殊字符转义
    /// </summary>
    /// <param name="s"></param>
    /// <returns></returns>
    public static String escapeQueryChars(String s)
    {
        StringBuilder sb = new StringBuilder();
        var ss = s.ToCharArray();
        foreach (var c in ss)
        {
            // These characters are part of the query syntax and must be escaped
            if (c == '\\' || c == '+' || c == '-' || c == '!' || c == '(' || c == ')' || c == ':'
              || c == '^' || c == '[' || c == ']' || c == '\"' || c == '{' || c == '}' || c == '~'
              || c == '*' || c == '?' || c == '|' || c == '&' || c == ';' || c == '/'
              )
            {
                sb.Append('\\');
            }
            sb.Append(c);
        }
        return sb.ToString();
    }