HybridDictionary 类
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
IDictionary通过使用集合较小时ListDictionary实现，然后在集合变大时切换到 AHashtable。
public ref class HybridDictionary : System::Collections::IDictionarypublic class HybridDictionary : System.Collections.IDictionary[System.Serializable]
public class HybridDictionary : System.Collections.IDictionarytype HybridDictionary = class
interface ICollection
interface IEnumerable
interface IDictionary[<System.Serializable>]
type HybridDictionary = class
interface IDictionary
interface ICollection
interface IEnumerablePublic Class HybridDictionary
Implements IDictionary- 继承
-
HybridDictionary
- 派生
- 属性
- 实现
示例
下面的代码示例演示了多个属性和方法 HybridDictionary。
using System;
using System.Collections;
using System.Collections.Specialized;
public class SamplesHybridDictionary {
public static void Main() {
// Creates and initializes a new HybridDictionary.
HybridDictionary myCol = new HybridDictionary();
myCol.Add( "Braeburn Apples", "1.49" );
myCol.Add( "Fuji Apples", "1.29" );
myCol.Add( "Gala Apples", "1.49" );
myCol.Add( "Golden Delicious Apples", "1.29" );
myCol.Add( "Granny Smith Apples", "0.89" );
myCol.Add( "Red Delicious Apples", "0.99" );
myCol.Add( "Plantain Bananas", "1.49" );
myCol.Add( "Yellow Bananas", "0.79" );
myCol.Add( "Strawberries", "3.33" );
myCol.Add( "Cranberries", "5.98" );
myCol.Add( "Navel Oranges", "1.29" );
myCol.Add( "Grapes", "1.99" );
myCol.Add( "Honeydew Melon", "0.59" );
myCol.Add( "Seedless Watermelon", "0.49" );
myCol.Add( "Pineapple", "1.49" );
myCol.Add( "Nectarine", "1.99" );
myCol.Add( "Plums", "1.69" );
myCol.Add( "Peaches", "1.99" );
// Display the contents of the collection using foreach. This is the preferred method.
Console.WriteLine( "Displays the elements using foreach:" );
PrintKeysAndValues1( myCol );
// Display the contents of the collection using the enumerator.
Console.WriteLine( "Displays the elements using the IDictionaryEnumerator:" );
PrintKeysAndValues2( myCol );
// Display the contents of the collection using the Keys, Values, Count, and Item properties.
Console.WriteLine( "Displays the elements using the Keys, Values, Count, and Item properties:" );
PrintKeysAndValues3( myCol );
// Copies the HybridDictionary to an array with DictionaryEntry elements.
DictionaryEntry[] myArr = new DictionaryEntry[myCol.Count];
myCol.CopyTo( myArr, 0 );
// Displays the values in the array.
Console.WriteLine( "Displays the elements in the array:" );
Console.WriteLine( " KEY VALUE" );
for ( int i = 0; i < myArr.Length; i++ )
Console.WriteLine( " {0,-25} {1}", myArr[i].Key, myArr[i].Value );
Console.WriteLine();
// Searches for a key.
if ( myCol.Contains( "Kiwis" ) )
Console.WriteLine( "The collection contains the key \"Kiwis\"." );
else
Console.WriteLine( "The collection does not contain the key \"Kiwis\"." );
Console.WriteLine();
// Deletes a key.
myCol.Remove( "Plums" );
Console.WriteLine( "The collection contains the following elements after removing \"Plums\":" );
PrintKeysAndValues1( myCol );
// Clears the entire collection.
myCol.Clear();
Console.WriteLine( "The collection contains the following elements after it is cleared:" );
PrintKeysAndValues1( myCol );
}
// Uses the foreach statement which hides the complexity of the enumerator.
// NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
public static void PrintKeysAndValues1( IDictionary myCol ) {
Console.WriteLine( " KEY VALUE" );
foreach ( DictionaryEntry de in myCol )
Console.WriteLine( " {0,-25} {1}", de.Key, de.Value );
Console.WriteLine();
}
// Uses the enumerator.
// NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
public static void PrintKeysAndValues2( IDictionary myCol ) {
IDictionaryEnumerator myEnumerator = myCol.GetEnumerator();
Console.WriteLine( " KEY VALUE" );
while ( myEnumerator.MoveNext() )
Console.WriteLine( " {0,-25} {1}", myEnumerator.Key, myEnumerator.Value );
Console.WriteLine();
}
// Uses the Keys, Values, Count, and Item properties.
public static void PrintKeysAndValues3( HybridDictionary myCol ) {
String[] myKeys = new String[myCol.Count];
myCol.Keys.CopyTo( myKeys, 0 );
Console.WriteLine( " INDEX KEY VALUE" );
for ( int i = 0; i < myCol.Count; i++ )
Console.WriteLine( " {0,-5} {1,-25} {2}", i, myKeys[i], myCol[myKeys[i]] );
Console.WriteLine();
}
}
/*
This code produces output similar to the following:
Displays the elements using foreach:
KEY VALUE
Strawberries 3.33
Yellow Bananas 0.79
Cranberries 5.98
Grapes 1.99
Granny Smith Apples 0.89
Seedless Watermelon 0.49
Honeydew Melon 0.59
Red Delicious Apples 0.99
Navel Oranges 1.29
Fuji Apples 1.29
Plantain Bananas 1.49
Gala Apples 1.49
Pineapple 1.49
Plums 1.69
Braeburn Apples 1.49
Peaches 1.99
Golden Delicious Apples 1.29
Nectarine 1.99
Displays the elements using the IDictionaryEnumerator:
KEY VALUE
Strawberries 3.33
Yellow Bananas 0.79
Cranberries 5.98
Grapes 1.99
Granny Smith Apples 0.89
Seedless Watermelon 0.49
Honeydew Melon 0.59
Red Delicious Apples 0.99
Navel Oranges 1.29
Fuji Apples 1.29
Plantain Bananas 1.49
Gala Apples 1.49
Pineapple 1.49
Plums 1.69
Braeburn Apples 1.49
Peaches 1.99
Golden Delicious Apples 1.29
Nectarine 1.99
Displays the elements using the Keys, Values, Count, and Item properties:
INDEX KEY VALUE
0 Strawberries 3.33
1 Yellow Bananas 0.79
2 Cranberries 5.98
3 Grapes 1.99
4 Granny Smith Apples 0.89
5 Seedless Watermelon 0.49
6 Honeydew Melon 0.59
7 Red Delicious Apples 0.99
8 Navel Oranges 1.29
9 Fuji Apples 1.29
10 Plantain Bananas 1.49
11 Gala Apples 1.49
12 Pineapple 1.49
13 Plums 1.69
14 Braeburn Apples 1.49
15 Peaches 1.99
16 Golden Delicious Apples 1.29
17 Nectarine 1.99
Displays the elements in the array:
KEY VALUE
Strawberries 3.33
Yellow Bananas 0.79
Cranberries 5.98
Grapes 1.99
Granny Smith Apples 0.89
Seedless Watermelon 0.49
Honeydew Melon 0.59
Red Delicious Apples 0.99
Navel Oranges 1.29
Fuji Apples 1.29
Plantain Bananas 1.49
Gala Apples 1.49
Pineapple 1.49
Plums 1.69
Braeburn Apples 1.49
Peaches 1.99
Golden Delicious Apples 1.29
Nectarine 1.99
The collection does not contain the key "Kiwis".
The collection contains the following elements after removing "Plums":
KEY VALUE
Strawberries 3.33
Yellow Bananas 0.79
Cranberries 5.98
Grapes 1.99
Granny Smith Apples 0.89
Seedless Watermelon 0.49
Honeydew Melon 0.59
Red Delicious Apples 0.99
Navel Oranges 1.29
Fuji Apples 1.29
Plantain Bananas 1.49
Gala Apples 1.49
Pineapple 1.49
Braeburn Apples 1.49
Peaches 1.99
Golden Delicious Apples 1.29
Nectarine 1.99
The collection contains the following elements after it is cleared:
KEY VALUE
*/
Imports System.Collections
Imports System.Collections.Specialized
Public Class SamplesHybridDictionary
Public Shared Sub Main()
' Creates and initializes a new HybridDictionary.
Dim myCol As New HybridDictionary()
myCol.Add("Braeburn Apples", "1.49")
myCol.Add("Fuji Apples", "1.29")
myCol.Add("Gala Apples", "1.49")
myCol.Add("Golden Delicious Apples", "1.29")
myCol.Add("Granny Smith Apples", "0.89")
myCol.Add("Red Delicious Apples", "0.99")
myCol.Add("Plantain Bananas", "1.49")
myCol.Add("Yellow Bananas", "0.79")
myCol.Add("Strawberries", "3.33")
myCol.Add("Cranberries", "5.98")
myCol.Add("Navel Oranges", "1.29")
myCol.Add("Grapes", "1.99")
myCol.Add("Honeydew Melon", "0.59")
myCol.Add("Seedless Watermelon", "0.49")
myCol.Add("Pineapple", "1.49")
myCol.Add("Nectarine", "1.99")
myCol.Add("Plums", "1.69")
myCol.Add("Peaches", "1.99")
' Display the contents of the collection using For Each. This is the preferred method.
Console.WriteLine("Displays the elements using For Each:")
PrintKeysAndValues1(myCol)
' Display the contents of the collection using the enumerator.
Console.WriteLine("Displays the elements using the IDictionaryEnumerator:")
PrintKeysAndValues2(myCol)
' Display the contents of the collection using the Keys, Values, Count, and Item properties.
Console.WriteLine("Displays the elements using the Keys, Values, Count, and Item properties:")
PrintKeysAndValues3(myCol)
' Copies the HybridDictionary to an array with DictionaryEntry elements.
Dim myArr(myCol.Count) As DictionaryEntry
myCol.CopyTo(myArr, 0)
' Displays the values in the array.
Console.WriteLine("Displays the elements in the array:")
Console.WriteLine(" KEY VALUE")
Dim i As Integer
For i = 0 To myArr.Length - 1
Console.WriteLine(" {0,-25} {1}", myArr(i).Key, myArr(i).Value)
Next i
Console.WriteLine()
' Searches for a key.
If myCol.Contains("Kiwis") Then
Console.WriteLine("The collection contains the key ""Kiwis"".")
Else
Console.WriteLine("The collection does not contain the key ""Kiwis"".")
End If
Console.WriteLine()
' Deletes a key.
myCol.Remove("Plums")
Console.WriteLine("The collection contains the following elements after removing ""Plums"":")
PrintKeysAndValues1(myCol)
' Clears the entire collection.
myCol.Clear()
Console.WriteLine("The collection contains the following elements after it is cleared:")
PrintKeysAndValues1(myCol)
End Sub
' Uses the For Each statement which hides the complexity of the enumerator.
' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
Public Shared Sub PrintKeysAndValues1(myCol As IDictionary)
Console.WriteLine(" KEY VALUE")
Dim de As DictionaryEntry
For Each de In myCol
Console.WriteLine(" {0,-25} {1}", de.Key, de.Value)
Next de
Console.WriteLine()
End Sub
' Uses the enumerator.
' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
Public Shared Sub PrintKeysAndValues2(myCol As IDictionary)
Dim myEnumerator As IDictionaryEnumerator = myCol.GetEnumerator()
Console.WriteLine(" KEY VALUE")
While myEnumerator.MoveNext()
Console.WriteLine(" {0,-25} {1}", myEnumerator.Key, myEnumerator.Value)
End While
Console.WriteLine()
End Sub
' Uses the Keys, Values, Count, and Item properties.
Public Shared Sub PrintKeysAndValues3(myCol As HybridDictionary)
Dim myKeys(myCol.Count) As [String]
myCol.Keys.CopyTo(myKeys, 0)
Console.WriteLine(" INDEX KEY VALUE")
Dim i As Integer
For i = 0 To myCol.Count - 1
Console.WriteLine(" {0,-5} {1,-25} {2}", i, myKeys(i), myCol(myKeys(i)))
Next i
Console.WriteLine()
End Sub
End Class
'This code produces output similar to the following:
'
'Displays the elements using For Each:
' KEY VALUE
' Strawberries 3.33
' Yellow Bananas 0.79
' Cranberries 5.98
' Grapes 1.99
' Granny Smith Apples 0.89
' Seedless Watermelon 0.49
' Honeydew Melon 0.59
' Red Delicious Apples 0.99
' Navel Oranges 1.29
' Fuji Apples 1.29
' Plantain Bananas 1.49
' Gala Apples 1.49
' Pineapple 1.49
' Plums 1.69
' Braeburn Apples 1.49
' Peaches 1.99
' Golden Delicious Apples 1.29
' Nectarine 1.99
'
'Displays the elements using the IDictionaryEnumerator:
' KEY VALUE
' Strawberries 3.33
' Yellow Bananas 0.79
' Cranberries 5.98
' Grapes 1.99
' Granny Smith Apples 0.89
' Seedless Watermelon 0.49
' Honeydew Melon 0.59
' Red Delicious Apples 0.99
' Navel Oranges 1.29
' Fuji Apples 1.29
' Plantain Bananas 1.49
' Gala Apples 1.49
' Pineapple 1.49
' Plums 1.69
' Braeburn Apples 1.49
' Peaches 1.99
' Golden Delicious Apples 1.29
' Nectarine 1.99
'
'Displays the elements using the Keys, Values, Count, and Item properties:
' INDEX KEY VALUE
' 0 Strawberries 3.33
' 1 Yellow Bananas 0.79
' 2 Cranberries 5.98
' 3 Grapes 1.99
' 4 Granny Smith Apples 0.89
' 5 Seedless Watermelon 0.49
' 6 Honeydew Melon 0.59
' 7 Red Delicious Apples 0.99
' 8 Navel Oranges 1.29
' 9 Fuji Apples 1.29
' 10 Plantain Bananas 1.49
' 11 Gala Apples 1.49
' 12 Pineapple 1.49
' 13 Plums 1.69
' 14 Braeburn Apples 1.49
' 15 Peaches 1.99
' 16 Golden Delicious Apples 1.29
' 17 Nectarine 1.99
'
'Displays the elements in the array:
' KEY VALUE
' Strawberries 3.33
' Yellow Bananas 0.79
' Cranberries 5.98
' Grapes 1.99
' Granny Smith Apples 0.89
' Seedless Watermelon 0.49
' Honeydew Melon 0.59
' Red Delicious Apples 0.99
' Navel Oranges 1.29
' Fuji Apples 1.29
' Plantain Bananas 1.49
' Gala Apples 1.49
' Pineapple 1.49
' Plums 1.69
' Braeburn Apples 1.49
' Peaches 1.99
' Golden Delicious Apples 1.29
' Nectarine 1.99
'
'The collection does not contain the key "Kiwis".
'
'The collection contains the following elements after removing "Plums":
' KEY VALUE
' Strawberries 3.33
' Yellow Bananas 0.79
' Cranberries 5.98
' Grapes 1.99
' Granny Smith Apples 0.89
' Seedless Watermelon 0.49
' Honeydew Melon 0.59
' Red Delicious Apples 0.99
' Navel Oranges 1.29
' Fuji Apples 1.29
' Plantain Bananas 1.49
' Gala Apples 1.49
' Pineapple 1.49
' Braeburn Apples 1.49
' Peaches 1.99
' Golden Delicious Apples 1.29
' Nectarine 1.99
'
'The collection contains the following elements after it is cleared:
' KEY VALUE
注解
对于字典中的元素数未知的情况，建议使用此类。 它利用改进的小型集合的性能，并提供了切换到一个ListDictionaryHashtable的灵活性，它处理更大的集合比ListDictionary。
如果集合的初始大小大于最佳大小 ListDictionary，则集合存储在一个 Hashtable 集合中，以避免从元素 ListDictionary 复制到 a Hashtable的开销。
构造函数接受一个布尔参数，该参数允许用户指定集合在比较字符串时是否忽略大小写。 如果集合区分大小写，则它使用密钥的实现 Object.GetHashCode 和 Object.Equals。 如果集合不区分大小写，则它执行简单的不区分大小写的比较，它只遵循固定区域性的大小写规则。 默认情况下，集合区分大小写。 有关固定区域性的详细信息，请参阅 System.Globalization.CultureInfo。
键不能为 null，但值可以。
foreach C# 语言（For Each在 Visual Basic 中）的语句返回集合中元素类型的对象。 由于每个元素都是键/值对，因此元素 HybridDictionary 类型不是键的类型或值的类型。 相反，元素类型为 DictionaryEntry. 例如：
foreach (DictionaryEntry de in myHybridDictionary)
{
//...
}
For Each de In myHybridDictionary
'...
Next
该 foreach 语句是枚举器周围的包装器，它只允许从集合（而不是写入到集合）进行读取。
构造函数
| 名称 | 说明 |
|---|---|
| HybridDictionary() |
创建一个空 HybridDictionary区分大小写的 。 |
| HybridDictionary(Boolean) |
创建具有指定大小写的空 HybridDictionary 。 |
| HybridDictionary(Int32, Boolean) |
创建具有指定的初始大小和区分大小写的 A HybridDictionary 。 |
| HybridDictionary(Int32) |
使用指定的初始大小创建区分 HybridDictionary 大小写。 |
属性
| 名称 | 说明 |
|---|---|
| Count |
获取包含在 .. 中的 HybridDictionary键/值对的数目。 |
| IsFixedSize |
获取一个值，该值指示是否 HybridDictionary 具有固定大小。 |
| IsReadOnly |
获取一个值，该值指示是否 HybridDictionary 为只读。 |
| IsSynchronized |
获取一个值，该值 HybridDictionary 指示是否同步（线程安全）。 |
| Item[Object] |
获取或设置与指定键关联的值。 |
| Keys |
获取一个 ICollection 包含 .. 中的 HybridDictionary键 |
| SyncRoot |
获取可用于同步对 . HybridDictionary的访问的对象。 |
| Values |
获取一个 ICollection 包含值中的 HybridDictionary值。 |
方法
| 名称 | 说明 |
|---|---|
| Add(Object, Object) |
将具有指定键和值的条目添加到 .HybridDictionary |
| Clear() |
从中 HybridDictionary删除所有条目。 |
| Contains(Object) |
确定 HybridDictionary 是否包含特定密钥。 |
| CopyTo(Array, Int32) |
将 HybridDictionary 条目复制到指定索引处的一维 Array 实例。 |
| Equals(Object) |
确定指定的对象是否等于当前对象。 (继承自 Object) |
| GetEnumerator() |
返回循环访问的IDictionaryEnumerator一个 HybridDictionary 。 |
| GetHashCode() |
用作默认哈希函数。 (继承自 Object) |
| GetType() |
获取当前实例的 Type。 (继承自 Object) |
| MemberwiseClone() |
创建当前 Object的浅表副本。 (继承自 Object) |
| Remove(Object) |
从 .. 中删除具有指定键的 HybridDictionary项。 |
| ToString() |
返回一个表示当前对象的字符串。 (继承自 Object) |
显式接口实现
| 名称 | 说明 |
|---|---|
| IEnumerable.GetEnumerator() |
返回循环访问的IEnumerator一个 HybridDictionary 。 |
扩展方法
| 名称 | 说明 |
|---|---|
| AsParallel(IEnumerable) |
启用查询的并行化。 |
| AsQueryable(IEnumerable) |
将 IEnumerable 转换为 IQueryable。 |
| Cast<TResult>(IEnumerable) |
将 IEnumerable 的元素强制转换为指定类型。 |
| OfType<TResult>(IEnumerable) |
根据指定类型筛选 IEnumerable 的元素。 |
适用于
线程安全性
此类型的公共静态（Shared 在 Visual Basic 中）成员是线程安全的。 不能保证任何实例成员是线程安全的。
此实现不提供同步的（线程安全）包装器HybridDictionary，但派生类可以创建其自己的使用属性的HybridDictionarySyncRoot同步版本。
通过集合进行枚举本质上不是线程安全的过程。 即使集合同步，其他线程仍可以修改集合，这会导致枚举器引发异常。 若要保证枚举期间的线程安全性，可以在整个枚举期间锁定集合，也可以捕获由其他线程所做的更改导致的异常。