將多個對象作爲值添加到字典中的鍵

Question

我的任務是讀取CSV文件並將文件內容放入字典中。

問題是讀入的每行都會有一個字典中已經存在的鍵。我被告知要將每行讀取的值（來自類對象）添加到與該行相關的密鑰中，該行是帳戶。

所以文件樣品看起來像這樣在每一行，大約有10個賬戶，但8000線：

帳戶1，值1，值2，值3

帳戶1，值1，值2，值3

所以我被要求做的是，當存在一個已經存在的獨特密鑰時，我需要在該對象（每行讀入）中添加該值。

但是當我被要求用一個對象做這件事時，這真的讓我感到困惑。我明白字典的方式是，如果鍵/值對是這樣的（字符串，整數）：

KEY1，5

KEY1，10

當我第二值添加到不同鍵它會看起來像這樣： key1,15 15

我沒有理解，當涉及到使用簡單的值，如int。

但是，如果我使用一個類，我的價值：

public class DataRecord 
    { 
     public string account; 
     public int open; 
     public int buy; 
     public int sell; 
     public double settleMM; 
     public string underlying; 
     public string symbol; 
    } 

這裏是我有我的應用程序迄今：

static void Main(string[] args) 
    { 
     double dParseSettleMM; 
     int iParseOpen; 
     int iParseBuy; 
     int iParseSell; 
     string sUnderlyingControl = string.Empty; 
     string sUnderlying = string.Empty; 
     string sAccount = string.Empty; 
     string sAccountControl = string.Empty; 

     var path = @"C:\Users\jhochbau\documents\visual studio 2015\Projects\CsvReader\CSVReaderList\Position_2016_02_25.0415.csv"; 

     Dictionary<string, DataRecord> vSummaryResults = new Dictionary<string, DataRecord>(); 

     //Sets up control to switch between sorted lists. 
     Console.WriteLine("Enter 1 to sort by Account, 2 to sort by Underlying, 3 to sort by Account and Underlying"); 
     string control = Console.ReadLine(); 

     //open reader 
     StreamReader r = new StreamReader(path); 
     StreamWriter vWriteFile = new StreamWriter("Positions2.csv"); 

     //Consume first line 
     r.ReadLine(); 

     //While loop to populate List with record Objects 
     while (!r.EndOfStream) 
     { 

      DataRecord records = new DataRecord(); 
      var line = r.ReadLine(); 
      var values = line.Split(','); 

      //Need to add into dictionary... 
      if (vSummaryResults.ContainsKey(records.account)) 
      { 
       vSummaryResults[records.account].open += records.open; 
      } 
      else 
      { 
       vSummaryResults.Add(records.account, records); 
      } 
     } 

    } 

編輯：這裏是我的具體問題。我被告知這段代碼已經有效，我想了解的是如何以及爲什麼，並嘗試將其視覺化以便理解它。

當我將其添加到字典中時，該類中每個字段發生了什麼？我的DataRecord類是否被用作值，只有這些字段的多個實例？

Answer 1

使您的字典值爲DataRecords的List（或其他集合）。

Dictionary<string, List<DataRecord>> vSummaryResults = new Dictionary<string, List<DataRecord>>(); 

然後，您可以將在執行過程中找到的任何新值添加到該列表中。

選項1：我繼續並修改代碼來執行此操作。

static void Main(string[] args) 
{ 
    double dParseSettleMM; 
    int iParseOpen; 
    int iParseBuy; 
    int iParseSell; 
    string sUnderlyingControl = string.Empty; 
    string sUnderlying = string.Empty; 
    string sAccount = string.Empty; 
    string sAccountControl = string.Empty; 

    var path = @"C:\Users\jhochbau\documents\visual studio 2015\Projects\CsvReader\CSVReaderList\Position_2016_02_25.0415.csv"; 

    Dictionary<string, List<DataRecord>> vSummaryResults = new Dictionary<string, List<DataRecord>>(); 

    //Sets up control to switch between sorted lists. 
    Console.WriteLine("Enter 1 to sort by Account, 2 to sort by Underlying, 3 to sort by Account and Underlying"); 
    string control = Console.ReadLine(); 

    //open reader 
    StreamReader r = new StreamReader(path); 
    StreamWriter vWriteFile = new StreamWriter("Positions2.csv"); 

    //Consume first line 
    r.ReadLine(); 

    //While loop to populate List with record Objects 
    while (!r.EndOfStream) 
    { 

     DataRecord records = new DataRecord(); 
     var line = r.ReadLine(); 
     var values = line.Split(','); 

     //Need to add into dictionary... 
     if (vSummaryResults.ContainsKey(records.account)) 
     { 
      vSummaryResults[records.account].Add(record); 
     } 
     else 
     { 
      vSummaryResults.Add(records.account, new List<DataRecord>()); 
      vSummaryResults[records.account].Add(record); 
     } 
    } 

} 

選項2：由於您不能使用選項1.這將序列化每個記錄並將其附加到該鍵的值。然後你可以用'，'來分割它，然後反序列化它。上述方法更好，但如果你不能使用它，那麼這應該工作。

static void Main(string[] args) 
{ 
    double dParseSettleMM; 
    int iParseOpen; 
    int iParseBuy; 
    int iParseSell; 
    string sUnderlyingControl = string.Empty; 
    string sUnderlying = string.Empty; 
    string sAccount = string.Empty; 
    string sAccountControl = string.Empty; 

    var path = @"C:\Users\jhochbau\documents\visual studio 2015\Projects\CsvReader\CSVReaderList\Position_2016_02_25.0415.csv"; 

    Dictionary<string, string> vSummaryResults = new Dictionary<string, string>(); 

    //Sets up control to switch between sorted lists. 
    Console.WriteLine("Enter 1 to sort by Account, 2 to sort by Underlying, 3 to sort by Account and Underlying"); 
    string control = Console.ReadLine(); 

    //open reader 
    StreamReader r = new StreamReader(path); 
    StreamWriter vWriteFile = new StreamWriter("Positions2.csv"); 

    //Consume first line 
    r.ReadLine(); 

    //While loop to populate List with record Objects 
    var serializer = new JavaScriptSerializer(); 
    while (!r.EndOfStream) 
    { 

     DataRecord records = new DataRecord(); 
     var line = r.ReadLine(); 
     var values = line.Split(','); 

     //Need to add into dictionary... 
     if (vSummaryResults.ContainsKey(records.account)) 
     { 
      vSummaryResults[records.account] += "," + serializer.Serialize(record); 
     } 
     else 
     { 
      vSummaryResults.Add(records.account, serializer.Serialize(record)); 
     } 
    } 

}