在C#中使用正则表达式匹配多行

Question

我有以下文字:

--------------030805090908050805080502
Content-Type: image/jpeg
Content-Transfer-Encoding: base64
Content-ID: <part16.07030906.00090703@highcontrast.ro>

/9j/4AAQSkZJRgABAgAAZABkAAD/7AARRHVja3kAAQAEAAAARgAA/+4ADkFkb2JlAGTAAAAA
/9j/4AAQSkZJRgABAgAAZABkAAD/7AARRHVja3kAAQAEAAAARgAA/+4ADkFkb2JlAGTAAAAA
QBQH/9k=
--------------030805090908050805080502
Content-Type: image/jpeg
Content-Transfer-Encoding: base64
Content-ID: <part17.07010805.02020809@highcontrast.ro>

/9j/4AAQSkZJRgABAgAAZABkAAD/7AARRHVja3kAAQAEAAAARgAA/+4ADkFkb2JlAGTAAAAA
/9j/4AAQSkZJRgABAgAAZABkAAD/7AARRHVja3kAAQAEAAAARgAA/+4ADkFkb2JlAGTAAAAA
juu41lRHFLufPCAID//Z
--------------030805090908050805080502--

我需要在C#2部分使用Regex:

1. 在第一次和第二次出现之间 "--------------030805090908050805080502"
2. 琴弦之间"--------------030805090908050805080502"和"--------------030805090908050805080502--"

我试过这个正则表达式:

--------------030805090908050805080502(\r.*)*--------------030805090908050805080502

但只在C#中regex.Matches(...)返回"--------------030805090908050805080502".

Answer 1

MatchCollection matches = Regex.Matches( text, @"([-]+\d{24})
                                                 (?<Content>.*?)
                                                 (?=\1)", 
                                         RegexOptions.IgnorePatternWhitespace | 
                                         RegexOptions.Singleline );

foreach ( Match match in matches )
{
    Console.WriteLine( 
        string.Format( "match: {0}\n\n", 
                       match.Groups[ "Content" ].Value ) );
}

更新:此表达式将查找两次出现的数字之间的所有匹配.如果号码必须是特定号码,而不是任何24位数字,请将"\ d {24}"更改为您要匹配的号码.