将文本的特定部分子串到对象列表的最有效方法是什么

Question

我有以下 vCard 文本，我的目的是将文本解析为 vCard 对象列表

BEGIN:VCARD
VERSION:2.1
N:Kleit;Ali;;;
FN:Ali Kleit
TEL;CELL:70101010
END:VCARD
BEGIN:VCARD
VERSION:2.1
N:Kleit;Saeed;;;
FN:Saeed Kleit
TEL;CELL:03494949
END:VCARD

以下是我的代码

 List<string> cards = new List<string>();

 if (text != null)
 {
     while (text.Length != 0)
     {
         int idx_begin = text.IndexOf("BEGIN:VCARD");

         if (idx_begin == -1)
             break;

         string endToken = "END:VCARD";
         int idx_end = text.IndexOf(endToken);

         if (idx_end == -1)
             break;

         string card = text.Substring(idx_begin, idx_end + endToken.Length);

         text = text.Substring(idx_end + endToken.Length);
         cards.Add(card);
     }
 }

接下来，使用Thought.vCards.vCard .NET Library 解析器解析每个找到的 vCard 文本

List<Thought.vCards.vCard> vCards = new List<Thought.vCards.vCard>();

List<string> failedStrings = new List<string>();

foreach (string card in cards)
{
    using (TextReader sr = new StringReader(card))
    {
        var vCard = new Thought.vCards.vCard(sr);

        if (vCard == null)
        {
            failedStrings.Add(card);
            continue;
        }

        vCards.Add(vCard);
    }
}

知道文本可能格式不正确，有没有更有效的方法来实现这一点？

Answer 1

这样的？

var vcards = File.ReadAllText(Path.Combine(Path.GetDirectoryName(Util.CurrentQueryPath), "Contacts.vcf"));

var vcardRe = new Regex(@"BEGIN:VCARD\s+(.+?)\s+END:VCARD", RegexOptions.Compiled | RegexOptions.Singleline);


var res = vcardRe.Matches(vcards)
.Cast<Match>()
.Select(x => x.Groups[0].Captures.Cast<Capture>().Select(c => c.Value).Last())
;

List<Thought.vCards.vCard> vCards = new List<Thought.vCards.vCard>();

List<string> failedStrings = new List<string>();

foreach(string card in res)
{
    using (TextReader sr = new StringReader(card))
    {
        var vCard = new Thought.vCards.vCard(sr);

        if (vCard == null)
        {
            failedStrings.Add(card);
            continue;
        }

        vCards.Add(vCard);
    }
}

vCards.Dump();