正则表达式匹配失败 求助

Question

$pattern="/(\d{4}\W\d{2}\W\d{1})\s({1}\d{2}\W\d{2}\W\d{2})\s(am|pm)/";
$str="today is 2010-12-5 12:12:12 pm";
匹配失败 求助！
Compilation failed: nothing to repeat at offset

Answer 1

$a = "abc";$b = "b";if ($a=~m/$b/){ print $a;}上述代码运行无误，怀疑楼主的$a里是不是没有引号？请楼主贴出完整代码，或者至少贴出$a和$b的内容。追问

$pattern="/(\d{4}\W\d{2}\W\d{1})\s({1}\d{2}\W\d{2}\W\d{2})\s(am|pm)/";
$str="today is 2010-12-5 12:12:12 pm";
if(preg_match($pattern, $str,$arr)){
echo "Success"
}else{
echo "Fail"
}

Answer 2

提示:没有内容要重复
应该是在"\s({1}"这个位置吧,这样写是错误的本回答被网友采纳