从对象列表中检索一个对象，但不是通过索引[]，而是通过字段名称

Question

最后你可以找到类和 Json 文件。

如何从对象列表中检索一个对象，而不是通过索引

[]

而是通过字段名称？我需要检索完整的对象。

反序列化 Json 文件后，我有一个连接列表：

// List of connections are in m_ListTest
Test m_listTest = new Test();

此时，我想通过传递连接名称来从该列表中检索特定元素

m_listTest.connections.name_connection == "Connection_A"

// Not by index
var ritorna_elemento_del_indice_selezionato_1 = m_listTest.connections[0];
// But by Name 
var ritorna_elemento_del_indice_selezionato_2 = m_listTest.connections.name_connection == "Connection_A";

Json 文件：

{
  "connections": [
    {
      "name_connection": "Connection_A",
      "imap_host": "imap.mail.com",
      "imap_user": "[email protected]",
      "imap_pass": "aaaaaaaaaa",
      "imap_SSL_TLS": 993,
      "folder_to_open": [ "folder_A_/subfolder1", "folder_A_/subfolder2" ],
      "excluded_emails": [ "[email protected]", "[email protected]", "[email protected]" ]
    },
    {
      "name_connection": "Connection_B",
      "imap_host": "imap.mail.com",
      "imap_user": "[email protected]",
      "imap_pass": "bbbbbbb",
      "imap_SSL_TLS": 993,
      "folder_to_open": [ "folder_B_/subfolder1", "folder_B_/subfolder2" ],
      "excluded_emails": [ "[email protected]", "[email protected]", "[email protected]" ]
    }
  ]
}

这是班级：

public class Test
{
    public Connection[] connections { get; set; }
}

public class Connection
{
    public string name_connection { get; set; }
    public string imap_host { get; set; }
    public string imap_user { get; set; }
    public string imap_pass { get; set; }
    public int imap_SSL_TLS { get; set; }
    public string[] folder_to_open { get; set; }
    public string[] excluded_emails { get; set; }
}

Answer 1

如前所述，简单的解决方案是使用 LINQ

public static TestExtensions
{
    public static Connection? GetConnectionByName( this Test test, string name )
      => test.connections.FirstOrDefault( x => x.name_connection == name );
}

// usage
var item = test.GetConnectionByName("ConnectionA");

如果您需要以非常高的频率，那么您可能需要构建更有效的查找：

var connectionByName = test.connections.ToDictionary(x => x.name_connection, x => x);
// ^^ Do this _once_ and store the dictionary.
var connection = connectionByName["ConnectionA"];