StringDictionary 類別
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
使用索引鍵和強型別為字串的值實作哈希表,而不是物件。
public ref class StringDictionary : System::Collections::IEnumerable
public class StringDictionary : System.Collections.IEnumerable
[System.Serializable]
public class StringDictionary : System.Collections.IEnumerable
type StringDictionary = class
interface IEnumerable
[<System.Serializable>]
type StringDictionary = class
interface IEnumerable
Public Class StringDictionary
Implements IEnumerable
- 繼承
-
StringDictionary
- 屬性
- 實作
範例
以下程式碼範例展示了 的 StringDictionary多項性質與方法 。
using System;
using System.Collections;
using System.Collections.Specialized;
public class SamplesStringDictionary {
public static void Main() {
// Creates and initializes a new StringDictionary.
StringDictionary myCol = new StringDictionary();
myCol.Add( "red", "rojo" );
myCol.Add( "green", "verde" );
myCol.Add( "blue", "azul" );
// 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 IEnumerator:" );
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 StringDictionary 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,-10} {1}", myArr[i].Key, myArr[i].Value );
Console.WriteLine();
// Searches for a value.
if ( myCol.ContainsValue( "amarillo" ) )
Console.WriteLine( "The collection contains the value \"amarillo\"." );
else
Console.WriteLine( "The collection does not contain the value \"amarillo\"." );
Console.WriteLine();
// Searches for a key and deletes it.
if ( myCol.ContainsKey( "green" ) )
myCol.Remove( "green" );
Console.WriteLine( "The collection contains the following elements after removing \"green\":" );
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( StringDictionary 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( StringDictionary myCol ) {
IEnumerator myEnumerator = myCol.GetEnumerator();
DictionaryEntry de;
Console.WriteLine( " KEY VALUE" );
while ( myEnumerator.MoveNext() ) {
de = (DictionaryEntry) myEnumerator.Current;
Console.WriteLine( " {0,-25} {1}", de.Key, de.Value );
}
Console.WriteLine();
}
// Uses the Keys, Values, Count, and Item properties.
public static void PrintKeysAndValues3( StringDictionary 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 the following output.
Displays the elements using foreach:
KEY VALUE
red rojo
blue azul
green verde
Displays the elements using the IEnumerator:
KEY VALUE
red rojo
blue azul
green verde
Displays the elements using the Keys, Values, Count, and Item properties:
INDEX KEY VALUE
0 red rojo
1 blue azul
2 green verde
Displays the elements in the array:
KEY VALUE
red rojo
blue azul
green verde
The collection does not contain the value "amarillo".
The collection contains the following elements after removing "green":
KEY VALUE
red rojo
blue azul
The collection contains the following elements after it is cleared:
KEY VALUE
*/
Imports System.Collections
Imports System.Collections.Specialized
Public Class SamplesStringDictionary
Public Shared Sub Main()
' Creates and initializes a new StringDictionary.
Dim myCol As New StringDictionary()
myCol.Add("red", "rojo")
myCol.Add("green", "verde")
myCol.Add("blue", "azul")
' 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 IEnumerator:")
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 StringDictionary 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,-10} {1}", myArr(i).Key, myArr(i).Value)
Next i
Console.WriteLine()
' Searches for a value.
If myCol.ContainsValue("amarillo") Then
Console.WriteLine("The collection contains the value ""amarillo"".")
Else
Console.WriteLine("The collection does not contain the value ""amarillo"".")
End If
Console.WriteLine()
' Searches for a key and deletes it.
If myCol.ContainsKey("green") Then
myCol.Remove("green")
End If
Console.WriteLine("The collection contains the following elements after removing ""green"":")
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 StringDictionary)
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 StringDictionary)
Dim myEnumerator As IEnumerator = myCol.GetEnumerator()
Dim de As DictionaryEntry
Console.WriteLine(" KEY VALUE")
While myEnumerator.MoveNext()
de = CType(myEnumerator.Current, DictionaryEntry)
Console.WriteLine(" {0,-25} {1}", de.Key, de.Value)
End While
Console.WriteLine()
End Sub
' Uses the Keys, Values, Count, and Item properties.
Public Shared Sub PrintKeysAndValues3(myCol As StringDictionary)
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 the following output.
'
'Displays the elements using For Each:
' KEY VALUE
' red rojo
' blue azul
' green verde
'
'Displays the elements using the IEnumerator:
' KEY VALUE
' red rojo
' blue azul
' green verde
'
'Displays the elements using the Keys, Values, Count, and Item properties:
' INDEX KEY VALUE
' 0 red rojo
' 1 blue azul
' 2 green verde
'
'Displays the elements in the array:
' KEY VALUE
' red rojo
' blue azul
' green verde
'
'
'The collection does not contain the value "amarillo".
'
'The collection contains the following elements after removing "green":
' KEY VALUE
' red rojo
' blue azul
'
'The collection contains the following elements after it is cleared:
' KEY VALUE
備註
鍵不能是,但值可以。null
此密鑰的處理方式不區分大小寫;在與字串字典一起使用之前,會先翻譯為小寫。
在 .NET Framework 1.0 版本中,此類別使用文化敏感字串比較。 然而,在 .NET Framework 1.1 版本及以後版本中,這個類別在比較字串時使用 CultureInfo.InvariantCulture。 欲了解更多文化如何影響比較與排序的資訊,請參閱 執行 Culture-Insensitive 字串操作。
建構函式
| 名稱 | Description |
|---|---|
| StringDictionary() |
初始化 StringDictionary 類別的新執行個體。 |
屬性
| 名稱 | Description |
|---|---|
| Count |
取得 中鍵值對 StringDictionary的數量。 |
| IsSynchronized |
取得值,指出是否同步存取 StringDictionary (線程安全)。 |
| Item[String] |
取得或設定與指定索引鍵相關聯的值。 |
| Keys |
會獲得一組 .StringDictionary |
| SyncRoot |
取得一個物件,可用來同步存取 StringDictionary。 |
| Values |
會得到一組值在 StringDictionary中。 |
方法
| 名稱 | Description |
|---|---|
| Add(String, String) |
將指定鍵與值的條目加入 StringDictionary。 |
| Clear() |
移除所有 的 StringDictionary。 |
| ContainsKey(String) |
判斷是否 StringDictionary 包含特定的金鑰。 |
| ContainsValue(String) |
判斷是否 StringDictionary 包含特定值。 |
| CopyTo(Array, Int32) |
將字串字典的值複製到指定索引的一維 Array 實例。 |
| Equals(Object) |
判斷指定的物件是否等於目前的物件。 (繼承來源 Object) |
| GetEnumerator() |
回傳一個枚舉子,會遍歷字串字典。 |
| GetHashCode() |
做為預設哈希函式。 (繼承來源 Object) |
| GetType() |
取得目前實例的 Type。 (繼承來源 Object) |
| MemberwiseClone() |
建立目前 Object的淺層複本。 (繼承來源 Object) |
| Remove(String) |
從字串字典中移除指定鍵的條目。 |
| ToString() |
傳回表示目前 物件的字串。 (繼承來源 Object) |
擴充方法
| 名稱 | Description |
|---|---|
| AsParallel(IEnumerable) |
啟用查詢的平行處理。 |
| AsQueryable(IEnumerable) |
將 IEnumerable 轉換成 IQueryable。 |
| Cast<TResult>(IEnumerable) |
將 IEnumerable 的項目轉換成指定的型別。 |
| OfType<TResult>(IEnumerable) |
根據指定的型別篩選 IEnumerable 的專案。 |
適用於
執行緒安全性
此類型的公用靜態 (Shared) 成員是安全線程。 任何實例成員都不保證具有執行緒安全性。
此實作未提供同步(執行緒安全)包裝器,StringDictionary但衍生類別可利用該StringDictionary屬性建立自己的同步版本SyncRoot。
透過集合列舉本質上不是安全線程的程式。 即使集合同步處理,其他線程仍然可以修改集合,這會導致列舉值擲回例外狀況。 若要保證列舉期間的線程安全性,您可以在整個列舉期間鎖定集合,或攔截其他線程所做的變更所產生的例外狀況。