合併兩個字典字典<字符串，字典<字符串，對象>>

Question

這是與這個問題有關，關於如何合併C＃中的兩個字典。展示了一個優雅的Linq解決方案，這很酷。

但是，該問題涉及到Dictionary<Object1, Object2>，而我有一個字典，其值爲Dictionary<string, Object>。

我要尋找一個解決方案用於合併拖Dictionary<string, Dictionary<string, Object>>，符合下列要求：

• 沒有兩個詞典的詞典結果複製鍵，

• 對於每個字典我認爲KEY分組可以成爲解決方案，但後一部分......

  internal static Dictionary<string, Dictionary<string, object>> OperationDic(Dictionary<string, Dictionary<string, object>> a, Dictionary<string, Dictionary<string, object>> b, string operation)` 
      { 
       switch (operation) 
       { 
        case "+": 
         var result = a.Concat(b).GroupBy(d => d.Key).ToDictionary (d => d.Key, d => d.First().Value); 
         return result;    
        default: 
  
         throw new Exception("Fail ..."); 
       }    
      } 
  

Answer 1

試試這個

VAR的結果= a.Concat（B）.GroupBy（C => c.Key）.ToDictionary>（

Answer 2

這不是對我很清楚你想要什麼。這種嘗試將兩個庫合併：

// first copy everything from a 
    var result = new Dictionary<string, Dictionary<string, object>>(a); 

    // now check to see if we can add stuff from b 
    foreach (var entryOuter in b) 
    { 
     Dictionary<string, object> existingValue; 
     if (result.TryGetValue(entryOuter.Key, out existingValue)) 
     { 
     // there's already an entry, see if we can add to it 
     foreach (var entryInner in entryOuter.Value) 
     { 
      if (existingValue.ContainsKey(entryInner.Key)) 
      throw new Exception("How can I merge two objects? Giving up."); 
      existingValue.Add(entryInner.Key, entryInner.Value); 
     } 
     } 
     else 
     { 
     // new entry 
     result.Add(entryOuter.Key, entryOuter.Value); 
     } 
    } 

    return result; 

您可能要添加檢查null。 a,b和existingValue（當它存在時）可以是null。

Answer 3

internal static Dictionary<string, Dictionary<string, object>> OperationDic(Dictionary<string, Dictionary<string, object>> a, Dictionary<string, Dictionary<string, object>> b, string operation) 
    { 
     var result = new Dictionary<string, Dictionary<string, object>>(a); 
     switch (operation) 
     { 
      case "+":     
      // now check to see if we can add stuff from b 
      foreach (var entryOuter in b) 
      { 
       Dictionary<string, object> existingValue; 
       if (result.TryGetValue(entryOuter.Key, out existingValue)) 
       { 
        Dictionary<string, object> Value = entryOuter.Value; 
        result[entryOuter.Key] = existingValue.Concat(Value).GroupBy(d => d.Key).ToDictionary(d => d.Key, d => d.First().Value); 
       } 
       else 
       { 
       // new entry 
       result.Add(entryOuter.Key, entryOuter.Value); 
       } 
      } 
      return result; 
      default:      
       throw new Exception("FAIL ..."); 
     } 
    } 

Answer 4

你應該問自己的第一個問題：合併兩個字典的結果有哪些類型？如果價值共享相同的密鑰，價值如何合併在一起？

這可能是這樣的：

public static Dictionary<TKey, IEnumerable<TValue>> Merge<TKey, TValue>(this IDictionary<TKey, TValue> this_, IDictionary<TKey, TValue> other) 
{ 
    return this_.Concat(other).  // IEnumerable<KeyValuePair<TKey, TValue>> 
     GroupBy(kvp => kvp.Key). // grouped by the keys 
     ToDictionary(grp => grp.Key, grp => grp.Select(kvp => kvp.Value).Distinct()); 
} 

所以你Dictionary<string, Dictionary<string, object>>型的兩個庫會去Dictionary<string, IEnumerable<Dictionary<string, object>>>。

然而，你的價值觀是字典，所以你可能想將它們合併：

public static Dictionary<TKey, IEnumerable<TValue>> Flatten<TKey, TValue>(IEnumerable<Dictionary<TKey, TValue>> dictionaries) 
{ 
    return dictionaries.SelectMany(d => d.Keys).Distinct().   // IEnumerable<TKey> containing all the keys 
     ToDictionary(key => key, 
      key => dictionaries.Where(d => d.ContainsKey(key)).  // find Dictionaries that contain the key 
       Select(d => d.First(kvp => kvp.Key.Equals(key))). // select that key (KeyValuePair<TKey, TValue>) 
       Select(kvp => kvp.Value));       // and the value 
} 

這需要一個IEnumerable<Dictionary<string, object>>並將其轉換爲一個Dictionary<string, IEnumerable<object>>。您現在可以針對Merge生成的每個字典值調用此方法。

的呼聲是：

Dictionary<string, IEnumerable<Dictionary<string, object>>> result1 = dic1.Merge(dic2); 
Dictionary<string, Dictionary<string, IEnumerable<object>>> result2 = dic1.Merge(dic2).ToDictionary(kvp => kvp.Key, kvp => Flatten(kvp.Value));