我是java和使用正则表达式的新手。该方法似乎是好的,它在主题字符串上找到结果,但是当我试图使用.group()获得实际字符串时,它是空的。下面是代码:
public String TestRegularExpression(){
try{
Pattern regex = Pattern.compile(pattern, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE);
Matcher regexMatcher = regex.matcher(sourceCode);
while (regexMatcher.find()) {
results += "<li>" + regexMatcher.group() + "</li>";
matches ++;
}
} catch (PatternSyntaxException ex) {
results = "<li><strong class='ibm-important'>Syntax error in the regular expression</strong></li>";
}
if(results == null){results = "<li><strong class='ibm-important'>No meta tags found</strong></li>";}
return "<h3>" + h3Title + " (" + matches + " found)</h3><ul>" + results + "</ul>";
}
任何帮助将非常感激!!
会不会是您没有看到输出?如果你直接输出匹配到HTML而不加引号,那只会在HTML代码中插入META标签,而web浏览器不会呈现它。