正则表达式匹配中文

public static bool IsFormDataExpression(string factorString)
        {
            //@"\[[0-9a-zA-Z\u4e00-\u9fa5]+\]\.\[[0-9a-zA-Z\u4e00-\u9fa5]+\]"
            Regex r = new Regex(FormDataExpressionStr);
            return r.IsMatch(factorString);
        }