Question

下面解释了问题。

PHP

public function DoSomething($content) {
    preg_match('/\s*\$\s*(.*)/is', $content, $matches);
    if(Count($matches) == 0)
        return $content;
    else 
        return false;
}

C＃

public static string DoSomething(string Content) {
    if (string.IsNullOrEmpty(Content)) 
        return null;

    string pattern = "pattern needed";

    if (Regex.Match(Content, pattern).Groups.Count > 1)
        return Content;
    else
        return null;
}

我的问题是正则表达式＆＃34; / \ s * \ $ \ s *（。*）/是＆＃34; 。它在C＃中无效。

如何在.NET中编写此代码？您是否知道在C＃中获得相同php结果的更简单方法？

提前致谢！

Answer 1

因此要设置pattern，您需要在@符号前面加上正确的逃避反斜杠。其次，/{pattern}/{flags}模式在.NET中不起作用;你需要拉出模式并发送类似的标志为RegexOptions：

string pattern = @"\s*\$\s*(.*)";

if (Regex.IsMatch(Content, pattern,
    RegexOptions.IgnoreCase | RegexOptions.Singleline))

Answer 2

以下是修改过的代码：

public static string DoSomething(string Content) {
    if (string.IsNullOrEmpty(Content)) 
        return null;

    string pattern = @"\s*\$\s*(.*)";

    if (Regex.Match(Content, pattern, RegexOptions.IgnoreCase | RegexOptions.Singleline).Groups.Count > 1)
        return Content;
    else
        return null;
}

我已从模式周围删除了正斜杠，并将标志转换为枚举值IgnoreCase和SingleLine（Dotall）。

Answer 3

Regex.IsMatch(subjectString, @"\A\s*\$\s*(.*)\z", RegexOptions.IgnoreCase | RegexOptions.Singleline)

<强>说明

Options: Case insensitive; Exact spacing; Dot matches line breaks; ^$ don't match at line breaks; Parentheses capture

Match a single character that is a “whitespace character” (any Unicode separator, tab, line feed, carriage return, vertical tab, form feed, next line) «\s*»
   Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»
Match the character “$” literally «\$»
Match a single character that is a “whitespace character” (any Unicode separator, tab, line feed, carriage return, vertical tab, form feed, next line) «\s*»
   Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»
Match the regex below and capture its match into backreference number 1 «(.*)»
   Match any single character «.*»
      Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»

\$1

Insert the backslash character «\»
Insert the text that was last matched by capturing group number 1 «$1»

Answer 4

我对你的转换有一些评论：

public static string DoSomething(string Content) {
    if (string.IsNullOrEmpty(Content)) 
        return null;

    string pattern = "pattern needed";

    if (Regex.Match(Content, pattern).Groups.Count > 1)
        return Content;
    else
        return null;
}

首先，如果您需要检查是否匹配，则应使用Regex.IsMatch。
要表示文字字符串，我们在字符串前加@，这有助于转义斜杠等。
要指定正则表达式选项，您可以将(?is)指定为速记表示，而不是使用函数的第二个参数。

所以最终的代码应该是这样的：

public static string DoSomething(string Content)
{
    if (string.IsNullOrEmpty(Content))
        return null;

    string pattern = @"(?is)\s*\$\s*(.*)";

    if (Regex.IsMatch(Content, pattern))
        return Content;
    else
        return null;
}

正则表达式：PHP到C＃|转换需要帮助

4 个答案: