SortedDictionary<TKey,TValue> 类
定义
重要
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表示根据键进行排序的键/值对的集合。
generic <typename TKey, typename TValue>
public ref class SortedDictionary : System::Collections::Generic::ICollection<System::Collections::Generic::KeyValuePair<TKey, TValue>>, System::Collections::Generic::IDictionary<TKey, TValue>, System::Collections::Generic::IEnumerable<System::Collections::Generic::KeyValuePair<TKey, TValue>>, System::Collections::Generic::IReadOnlyCollection<System::Collections::Generic::KeyValuePair<TKey, TValue>>, System::Collections::Generic::IReadOnlyDictionary<TKey, TValue>, System::Collections::IDictionarygeneric <typename TKey, typename TValue>
public ref class SortedDictionary : System::Collections::Generic::ICollection<System::Collections::Generic::KeyValuePair<TKey, TValue>>, System::Collections::Generic::IDictionary<TKey, TValue>, System::Collections::Generic::IEnumerable<System::Collections::Generic::KeyValuePair<TKey, TValue>>, System::Collections::IDictionarypublic class SortedDictionary<TKey,TValue> : System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IDictionary<TKey,TValue>, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IReadOnlyCollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IReadOnlyDictionary<TKey,TValue>, System.Collections.IDictionary[System.Serializable]
public class SortedDictionary<TKey,TValue> : System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IDictionary<TKey,TValue>, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.IDictionary[System.Serializable]
public class SortedDictionary<TKey,TValue> : System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IDictionary<TKey,TValue>, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IReadOnlyCollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IReadOnlyDictionary<TKey,TValue>, System.Collections.IDictionarypublic class SortedDictionary<TKey,TValue> : System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.Generic.IDictionary<TKey,TValue>, System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TValue>>, System.Collections.IDictionarytype SortedDictionary<'Key, 'Value> = class
interface ICollection<KeyValuePair<'Key, 'Value>>
interface seq<KeyValuePair<'Key, 'Value>>
interface IEnumerable
interface IDictionary<'Key, 'Value>
interface IReadOnlyCollection<KeyValuePair<'Key, 'Value>>
interface IReadOnlyDictionary<'Key, 'Value>
interface ICollection
interface IDictionary[<System.Serializable>]
type SortedDictionary<'Key, 'Value> = class
interface IDictionary<'Key, 'Value>
interface ICollection<KeyValuePair<'Key, 'Value>>
interface seq<KeyValuePair<'Key, 'Value>>
interface IDictionary
interface ICollection
interface IEnumerable[<System.Serializable>]
type SortedDictionary<'Key, 'Value> = class
interface IDictionary<'Key, 'Value>
interface ICollection<KeyValuePair<'Key, 'Value>>
interface seq<KeyValuePair<'Key, 'Value>>
interface IEnumerable
interface IDictionary
interface ICollection
interface IReadOnlyDictionary<'Key, 'Value>
interface IReadOnlyCollection<KeyValuePair<'Key, 'Value>>type SortedDictionary<'Key, 'Value> = class
interface IDictionary<'Key, 'Value>
interface ICollection<KeyValuePair<'Key, 'Value>>
interface seq<KeyValuePair<'Key, 'Value>>
interface IDictionary
interface ICollection
interface IEnumerable[<System.Serializable>]
type SortedDictionary<'Key, 'Value> = class
interface IDictionary<'Key, 'Value>
interface IDictionary
interface IReadOnlyDictionary<'Key, 'Value>
interface ICollection<KeyValuePair<'Key, 'Value>>
interface seq<KeyValuePair<'Key, 'Value>>
interface IEnumerable
interface ICollection
interface IReadOnlyCollection<KeyValuePair<'Key, 'Value>>Public Class SortedDictionary(Of TKey, TValue)
Implements ICollection(Of KeyValuePair(Of TKey, TValue)), IDictionary, IDictionary(Of TKey, TValue), IEnumerable(Of KeyValuePair(Of TKey, TValue)), IReadOnlyCollection(Of KeyValuePair(Of TKey, TValue)), IReadOnlyDictionary(Of TKey, TValue)Public Class SortedDictionary(Of TKey, TValue)
Implements ICollection(Of KeyValuePair(Of TKey, TValue)), IDictionary, IDictionary(Of TKey, TValue), IEnumerable(Of KeyValuePair(Of TKey, TValue))类型参数
- TKey
字典中的键的类型。
- TValue
字典中的值的类型。
- 继承
-
SortedDictionary<TKey,TValue>
- 属性
- 实现
-
ICollection<KeyValuePair<TKey,TValue>> IDictionary<TKey,TValue> IEnumerable<KeyValuePair<TKey,TValue>> IEnumerable<T> IReadOnlyCollection<KeyValuePair<TKey,TValue>> IReadOnlyDictionary<TKey,TValue> ICollection IDictionary IEnumerable
示例
下面的代码示例使用字符串键创建一个空 SortedDictionary<TKey,TValue> 字符串，并使用 Add 方法添加一些元素。 该示例演示方法在 Add 尝试添加重复键时引发 ArgumentException 。
该示例使用 Item[] C#) 中索引器 (属性来检索值，演示 KeyNotFoundException 在请求的键不存在时引发 ，并显示可以替换与键关联的值。
该示例演示如何使用TryGetValue方法作为更高效的方法来检索值，如果程序必须经常尝试在字典中，不并显示如何使用ContainsKey方法来测试某个键是否存在之前调用Add方法。
该示例演示如何枚举字典中的键和值，以及如何使用 Keys 属性和 属性单独枚举键和 Values 值。
最后，该示例演示 了 Remove 方法。
using System;
using System.Collections.Generic;
public class Example
{
public static void Main()
{
// Create a new sorted dictionary of strings, with string
// keys.
SortedDictionary<string, string> openWith =
new SortedDictionary<string, string>();
// Add some elements to the dictionary. There are no
// duplicate keys, but some of the values are duplicates.
openWith.Add("txt", "notepad.exe");
openWith.Add("bmp", "paint.exe");
openWith.Add("dib", "paint.exe");
openWith.Add("rtf", "wordpad.exe");
// The Add method throws an exception if the new key is
// already in the dictionary.
try
{
openWith.Add("txt", "winword.exe");
}
catch (ArgumentException)
{
Console.WriteLine("An element with Key = \"txt\" already exists.");
}
// The Item property is another name for the indexer, so you
// can omit its name when accessing elements.
Console.WriteLine("For key = \"rtf\", value = {0}.",
openWith["rtf"]);
// The indexer can be used to change the value associated
// with a key.
openWith["rtf"] = "winword.exe";
Console.WriteLine("For key = \"rtf\", value = {0}.",
openWith["rtf"]);
// If a key does not exist, setting the indexer for that key
// adds a new key/value pair.
openWith["doc"] = "winword.exe";
// The indexer throws an exception if the requested key is
// not in the dictionary.
try
{
Console.WriteLine("For key = \"tif\", value = {0}.",
openWith["tif"]);
}
catch (KeyNotFoundException)
{
Console.WriteLine("Key = \"tif\" is not found.");
}
// When a program often has to try keys that turn out not to
// be in the dictionary, TryGetValue can be a more efficient
// way to retrieve values.
string value = "";
if (openWith.TryGetValue("tif", out value))
{
Console.WriteLine("For key = \"tif\", value = {0}.", value);
}
else
{
Console.WriteLine("Key = \"tif\" is not found.");
}
// ContainsKey can be used to test keys before inserting
// them.
if (!openWith.ContainsKey("ht"))
{
openWith.Add("ht", "hypertrm.exe");
Console.WriteLine("Value added for key = \"ht\": {0}",
openWith["ht"]);
}
// When you use foreach to enumerate dictionary elements,
// the elements are retrieved as KeyValuePair objects.
Console.WriteLine();
foreach( KeyValuePair<string, string> kvp in openWith )
{
Console.WriteLine("Key = {0}, Value = {1}",
kvp.Key, kvp.Value);
}
// To get the values alone, use the Values property.
SortedDictionary<string, string>.ValueCollection valueColl =
openWith.Values;
// The elements of the ValueCollection are strongly typed
// with the type that was specified for dictionary values.
Console.WriteLine();
foreach( string s in valueColl )
{
Console.WriteLine("Value = {0}", s);
}
// To get the keys alone, use the Keys property.
SortedDictionary<string, string>.KeyCollection keyColl =
openWith.Keys;
// The elements of the KeyCollection are strongly typed
// with the type that was specified for dictionary keys.
Console.WriteLine();
foreach( string s in keyColl )
{
Console.WriteLine("Key = {0}", s);
}
// Use the Remove method to remove a key/value pair.
Console.WriteLine("\nRemove(\"doc\")");
openWith.Remove("doc");
if (!openWith.ContainsKey("doc"))
{
Console.WriteLine("Key \"doc\" is not found.");
}
}
}
/* This code example produces the following output:
An element with Key = "txt" already exists.
For key = "rtf", value = wordpad.exe.
For key = "rtf", value = winword.exe.
Key = "tif" is not found.
Key = "tif" is not found.
Value added for key = "ht": hypertrm.exe
Key = bmp, Value = paint.exe
Key = dib, Value = paint.exe
Key = doc, Value = winword.exe
Key = ht, Value = hypertrm.exe
Key = rtf, Value = winword.exe
Key = txt, Value = notepad.exe
Value = paint.exe
Value = paint.exe
Value = winword.exe
Value = hypertrm.exe
Value = winword.exe
Value = notepad.exe
Key = bmp
Key = dib
Key = doc
Key = ht
Key = rtf
Key = txt
Remove("doc")
Key "doc" is not found.
*/
Imports System.Collections.Generic
Public Class Example
Public Shared Sub Main()
' Create a new sorted dictionary of strings, with string
' keys.
Dim openWith As New SortedDictionary(Of String, String)
' Add some elements to the dictionary. There are no
' duplicate keys, but some of the values are duplicates.
openWith.Add("txt", "notepad.exe")
openWith.Add("bmp", "paint.exe")
openWith.Add("dib", "paint.exe")
openWith.Add("rtf", "wordpad.exe")
' The Add method throws an exception if the new key is
' already in the dictionary.
Try
openWith.Add("txt", "winword.exe")
Catch
Console.WriteLine("An element with Key = ""txt"" already exists.")
End Try
' The Item property is the default property, so you
' can omit its name when accessing elements.
Console.WriteLine("For key = ""rtf"", value = {0}.", _
openWith("rtf"))
' The default Item property can be used to change the value
' associated with a key.
openWith("rtf") = "winword.exe"
Console.WriteLine("For key = ""rtf"", value = {0}.", _
openWith("rtf"))
' If a key does not exist, setting the default Item property
' for that key adds a new key/value pair.
openWith("doc") = "winword.exe"
' The default Item property throws an exception if the requested
' key is not in the dictionary.
Try
Console.WriteLine("For key = ""tif"", value = {0}.", _
openWith("tif"))
Catch
Console.WriteLine("Key = ""tif"" is not found.")
End Try
' When a program often has to try keys that turn out not to
' be in the dictionary, TryGetValue can be a more efficient
' way to retrieve values.
Dim value As String = ""
If openWith.TryGetValue("tif", value) Then
Console.WriteLine("For key = ""tif"", value = {0}.", value)
Else
Console.WriteLine("Key = ""tif"" is not found.")
End If
' ContainsKey can be used to test keys before inserting
' them.
If Not openWith.ContainsKey("ht") Then
openWith.Add("ht", "hypertrm.exe")
Console.WriteLine("Value added for key = ""ht"": {0}", _
openWith("ht"))
End If
' When you use foreach to enumerate dictionary elements,
' the elements are retrieved as KeyValuePair objects.
Console.WriteLine()
For Each kvp As KeyValuePair(Of String, String) In openWith
Console.WriteLine("Key = {0}, Value = {1}", _
kvp.Key, kvp.Value)
Next kvp
' To get the values alone, use the Values property.
Dim valueColl _
As SortedDictionary(Of String, String).ValueCollection = _
openWith.Values
' The elements of the ValueCollection are strongly typed
' with the type that was specified for dictionary values.
Console.WriteLine()
For Each s As String In valueColl
Console.WriteLine("Value = {0}", s)
Next s
' To get the keys alone, use the Keys property.
Dim keyColl _
As SortedDictionary(Of String, String).KeyCollection = _
openWith.Keys
' The elements of the KeyCollection are strongly typed
' with the type that was specified for dictionary keys.
Console.WriteLine()
For Each s As String In keyColl
Console.WriteLine("Key = {0}", s)
Next s
' Use the Remove method to remove a key/value pair.
Console.WriteLine(vbLf + "Remove(""doc"")")
openWith.Remove("doc")
If Not openWith.ContainsKey("doc") Then
Console.WriteLine("Key ""doc"" is not found.")
End If
End Sub
End Class
' This code example produces the following output:
'
'An element with Key = "txt" already exists.
'For key = "rtf", value = wordpad.exe.
'For key = "rtf", value = winword.exe.
'Key = "tif" is not found.
'Key = "tif" is not found.
'Value added for key = "ht": hypertrm.exe
'
'Key = bmp, Value = paint.exe
'Key = dib, Value = paint.exe
'Key = doc, Value = winword.exe
'Key = ht, Value = hypertrm.exe
'Key = rtf, Value = winword.exe
'Key = txt, Value = notepad.exe
'
'Value = paint.exe
'Value = paint.exe
'Value = winword.exe
'Value = hypertrm.exe
'Value = winword.exe
'Value = notepad.exe
'
'Key = bmp
'Key = dib
'Key = doc
'Key = ht
'Key = rtf
'Key = txt
'
'Remove("doc")
'Key "doc" is not found.
'
注解
泛 SortedDictionary<TKey,TValue> 型类是具有 O (log n) 检索的二进制搜索树，其中 n 是字典中的元素数。 在这方面，它类似于 SortedList<TKey,TValue> 泛型类。 这两个类具有相似的对象模型，并且都具有 O (log n) 检索。 这两个类的不同之处在于内存使用情况和插入和删除速度：
SortedList<TKey,TValue> 使用的内存少于 SortedDictionary<TKey,TValue>。
SortedDictionary<TKey,TValue>具有更快的未排序数据的插入和删除操作：O (log n) ，而不是 O (n) 。SortedList<TKey,TValue>
如果一次性从已排序的数据填充列表， SortedList<TKey,TValue> 比 SortedDictionary<TKey,TValue>快。
每个键/值对都可以作为 KeyValuePair<TKey,TValue> 结构或通过 DictionaryEntry 非泛型 IDictionary 接口检索。
键必须是不可变的，只要它们用作 中的键。SortedDictionary<TKey,TValue> 中的每个键都必须是唯一的 SortedDictionary<TKey,TValue> 。 如果值类型是引用类型TValue，则键不能为 null，但值可以是 。
SortedDictionary<TKey,TValue> 需要比较器实现来执行键比较。 可以使用接受comparer参数的构造函数指定泛型接口的IComparer<T>实现;如果不指定实现，则使用默认泛型比较器Comparer<T>.Default。 如果 类型 TKey 实现 System.IComparable<T> 泛型接口，则默认比较器使用该实现。
foreach Visual Basic) C++ For Each 中 C# 语言 (for each 语句返回集合中元素的类型的对象。 由于 的每个 SortedDictionary<TKey,TValue> 元素都是键/值对，因此元素类型不是键的类型或值的类型。 相反，元素类型为 KeyValuePair<TKey,TValue>。 以下代码演示 C#、C++ 和 Visual Basic 语法。
for each(KeyValuePair<String^, String^> kvp in myDictionary)
{
Console::WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}
foreach( KeyValuePair<string, string> kvp in myDictionary )
{
Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}
For Each kvp As KeyValuePair(Of String, String) In myDictionary
Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value)
Next kvp
语句 foreach 是枚举器的包装器，它只允许从集合中读取，而不允许写入集合。
构造函数
| SortedDictionary<TKey,TValue>() |
初始化 SortedDictionary<TKey,TValue> 类的一个新实例，该实例为空并对键类型使用默认 IComparer<T> 实现。 |
| SortedDictionary<TKey,TValue>(IComparer<TKey>) |
初始化 SortedDictionary<TKey,TValue> 类的一个新实例，该实例为空并对比较键使用指定 IComparer<T> 实现。 |
| SortedDictionary<TKey,TValue>(IDictionary<TKey,TValue>) |
初始化 SortedDictionary<TKey,TValue> 类的新实例，该实例包含从指定的 IDictionary<TKey,TValue> 中复制的元素，并使用键类型的默认 IComparer<T> 实现。 |
| SortedDictionary<TKey,TValue>(IDictionary<TKey,TValue>, IComparer<TKey>) |
初始化 SortedDictionary<TKey,TValue> 类的新实例，该实例包含从指定的 IDictionary<TKey,TValue> 中复制的元素，并使用指定的 IComparer<T> 实现来比较键。 |
属性
| Comparer |
获取用于对 IComparer<T> 的元素进行排序的 SortedDictionary<TKey,TValue>。 |
| Count |
获取包含在 SortedDictionary<TKey,TValue> 中的键/值对的数目。 |
| Item[TKey] |
获取或设置与指定的键关联的值。 |
| Keys |
获得一个包含 SortedDictionary<TKey,TValue> 中的键的集合。 |
| Values |
获得一个包含 SortedDictionary<TKey,TValue> 中的值的集合。 |
方法
| Add(TKey, TValue) |
将带有指定键和值的元素添加到 SortedDictionary<TKey,TValue> 中。 |
| Clear() |
从 SortedDictionary<TKey,TValue> 中移除所有元素。 |
| ContainsKey(TKey) |
确定是否 SortedDictionary<TKey,TValue> 包含带有指定键的元素。 |
| ContainsValue(TValue) |
确定 SortedDictionary<TKey,TValue> 是否包含具有指定值的元素。 |
| CopyTo(KeyValuePair<TKey,TValue>[], Int32) |
从指定的索引处开始，将 SortedDictionary<TKey,TValue> 的元素复制到指定的 KeyValuePair<TKey,TValue> 结构的数组中。 |
| Equals(Object) |
确定指定对象是否等于当前对象。 (继承自 Object) |
| GetEnumerator() |
返回循环访问 SortedDictionary<TKey,TValue> 的枚举数。 |
| GetHashCode() |
作为默认哈希函数。 (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(TKey) |
从 SortedDictionary<TKey,TValue> 中移除包含指定键的元素。 |
| ToString() |
返回表示当前对象的字符串。 (继承自 Object) |
| TryGetValue(TKey, TValue) |
获取与指定键关联的值。 |
显式接口实现
扩展方法
适用于
线程安全性
Visual Basic 中的公共静态 (Shared) 此类型的成员是线程安全的。 但不保证所有实例成员都是线程安全的。
SortedDictionary<TKey,TValue>只要集合未修改，就可以同时支持多个读取器。 即便如此，从本质上讲，通过集合枚举并不是线程安全的过程。 若要确保枚举过程中的线程安全性，可以在整个枚举过程中锁定集合。 若要允许多个线程访问集合以进行读写操作，则必须实现自己的同步。