c# - 如果键子串存在则返回字典值

Question

如果键包含一个与字符串查找一半匹配的字符串，我想从字典中返回值。

private readonly Dictionary<string, string> _ipAddressesDictionary = new Dictionary<string, string>()
{
       {"ip.qwer4.abc5.somename", "6x.x.00.xx"},
       {"ip.qwer3.abc1.somename", "6x.3.xx.xx"},
}

例如，

我有一个字符串“abc1.somename”，我正在构建如下逻辑 - 目前不起作用 - 为我获取值给定的键名包含该子字符串。我希望得到“6x.3.xx.xx”。

public string LookUpPeerIp(string deviceName)
{
    var value = _ipAddressesDictionary.Keys.Contains(deviceName);

    return value.ToString();
}

编辑:

抱歉，伙计们，忘记提及传入的字符串以进行查找也不完全匹配。它附加了一个 .co.uk :(

所以它将是 abc1.somename.co.uk 但字典有 ip.qwer3.abc1.somename 没有 .co.uk

Answer 1

在线尝试 https://dotnetfiddle.net/q6E1wR

这将切割正确的点 - 我的回答:

用法:

Console.WriteLine("--first");
Console.WriteLine(LookupByPrefix("abc1.somename.co.uk"));
Console.WriteLine("--many");
string[] many = LookupByPrefixMany("abc1.somename.co.uk");
foreach(string ip in many)
    Console.WriteLine(ip);

对于单个结果:

public string LookupByPrefix(string domainName)
{
    string[] dotDomains = domainName.Split('.');

    for(int matchCount = dotDomains.Length; matchCount > 0; matchCount--)
    {
        string[] ret = LookUpPeerIpMany(string.Join(".", dotDomains.Take(matchCount)));
        if(ret != null && ret.Length > 0) return ret.SingleOrDefault();
    }

    return null;
}

对于多个结果:

public string[] LookupByPrefixMany(string domainName)
{
    string[] dotDomains = domainName.Split('.');

    for(int matchCount = dotDomains.Length; matchCount > 0; matchCount--)
    {
        string[] ret = LookUpPeerIpMany(string.Join(".", dotDomains.Take(matchCount)));
        if(ret != null && ret.Length > 0) return ret;
    }

    return null;
}

依赖:

public string[] LookUpPeerIpMany(string deviceName)
{
    return _ipAddressesDictionary
           .Where(q=>q.Key.Contains(deviceName)).Select(q=>q.Value).ToArray();
}

很高兴为您服务!