ArrayList.FixedSize Метод

  • Ссылка

Определение

Пространство имен:
System.Collections
Сборки:
mscorlib.dll, System.Collections.NonGeneric.dll
Сборка:
System.Runtime.dll
Сборка:
System.Collections.NonGeneric.dll
Сборка:
System.Runtime.Extensions.dll
Сборка:
mscorlib.dll
Сборка:
netstandard.dll

Возвращает оболочку списка фиксированного размера, в которой элементы можно изменять, но нельзя добавлять или удалять.

Перегрузки

FixedSize(ArrayList)

Возвращает оболочку ArrayList фиксированного размера.
FixedSize(IList)

Возвращает оболочку IList фиксированного размера.

FixedSize(ArrayList)

Исходный код:
ArrayList.cs
Исходный код:
ArrayList.cs
Исходный код:
ArrayList.cs

Возвращает оболочку ArrayList фиксированного размера.

public:
 static System::Collections::ArrayList ^ FixedSize(System::Collections::ArrayList ^ list);
public static System.Collections.ArrayList FixedSize (System.Collections.ArrayList list);
static member FixedSize : System.Collections.ArrayList -> System.Collections.ArrayList
Public Shared Function FixedSize (list As ArrayList) As ArrayList

Параметры

list
ArrayList

Класс ArrayList, для которого создается оболочка.

Возвращаемое значение

ArrayList

Оболочка ArrayList фиксированного размера.

Исключения

ArgumentNullException

list имеет значение null.

Примеры

В следующем примере кода показано, как создать оболочку фиксированного ArrayListразмера вокруг .

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList, char mySeparator );
int main()
{
   
   // Creates and initializes a new ArrayList.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "The" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );
   
   // Create a fixed-size wrapper around the ArrayList.
   ArrayList^ myFixedSizeAL = ArrayList::FixedSize( myAL );
   
   // Display whether the ArrayLists have a fixed size or not.
   Console::WriteLine( "myAL {0}.", myAL->IsFixedSize ? (String^)"has a fixed size" : "does not have a fixed size" );
   Console::WriteLine( "myFixedSizeAL {0}.", myFixedSizeAL->IsFixedSize ? (String^)"has a fixed size" : "does not have a fixed size" );
   Console::WriteLine();
   
   // Display both ArrayLists.
   Console::WriteLine( "Initially," );
   Console::Write( "Standard  :" );
   PrintValues( myAL, ' ' );
   Console::Write( "Fixed size:" );
   PrintValues( myFixedSizeAL, ' ' );
   
   // Sort is allowed in the fixed-size ArrayList.
   myFixedSizeAL->Sort();
   
   // Display both ArrayLists.
   Console::WriteLine( "After Sort," );
   Console::Write( "Standard  :" );
   PrintValues( myAL, ' ' );
   Console::Write( "Fixed size:" );
   PrintValues( myFixedSizeAL, ' ' );
   
   // Reverse is allowed in the fixed-size ArrayList.
   myFixedSizeAL->Reverse();
   
   // Display both ArrayLists.
   Console::WriteLine( "After Reverse," );
   Console::Write( "Standard  :" );
   PrintValues( myAL, ' ' );
   Console::Write( "Fixed size:" );
   PrintValues( myFixedSizeAL, ' ' );
   
   // Add an element to the standard ArrayList.
   myAL->Add( "AddMe" );
   
   // Display both ArrayLists.
   Console::WriteLine( "After adding to the standard ArrayList," );
   Console::Write( "Standard  :" );
   PrintValues( myAL, ' ' );
   Console::Write( "Fixed size:" );
   PrintValues( myFixedSizeAL, ' ' );
   Console::WriteLine();
   
   // Adding or inserting elements to the fixed-size ArrayList throws an exception.
   try
   {
      myFixedSizeAL->Add( "AddMe2" );
   }
   catch ( Exception^ myException ) 
   {
      Console::WriteLine( "Exception: {0}", myException );
   }

   try
   {
      myFixedSizeAL->Insert( 3, "InsertMe" );
   }
   catch ( Exception^ myException ) 
   {
      Console::WriteLine( "Exception: {0}", myException );
   }

}

void PrintValues( IEnumerable^ myList, char mySeparator )
{
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "{0}{1}", mySeparator, obj );
   }

   Console::WriteLine();
}

/*
 This code produces the following output.
 
 myAL does not have a fixed size.
 myFixedSizeAL has a fixed size.

 Initially,
 Standard  : The quick brown fox jumps over the lazy dog
 Fixed size: The quick brown fox jumps over the lazy dog
 After Sort,
 Standard  : brown dog fox jumps lazy over quick the The
 Fixed size: brown dog fox jumps lazy over quick the The
 After Reverse,
 Standard  : The the quick over lazy jumps fox dog brown
 Fixed size: The the quick over lazy jumps fox dog brown
 After adding to the standard ArrayList,
 Standard  : The the quick over lazy jumps fox dog brown AddMe
 Fixed size: The the quick over lazy jumps fox dog brown AddMe

 Exception: System.NotSupportedException: Collection was of a fixed size.
    at System.Collections.FixedSizeArrayList.Add(Object obj)
    at SamplesArrayList.Main()
 Exception: System.NotSupportedException: Collection was of a fixed size.
    at System.Collections.FixedSizeArrayList.Insert(Int32 index, Object obj)
    at SamplesArrayList.Main()

 */

using System;
using System.Collections;
public class SamplesArrayList  {

   public static void Main()  {

      // Creates and initializes a new ArrayList.
      ArrayList myAL = new ArrayList();
      myAL.Add( "The" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );

      // Create a fixed-size wrapper around the ArrayList.
      ArrayList myFixedSizeAL = ArrayList.FixedSize( myAL );

      // Display whether the ArrayLists have a fixed size or not.
      Console.WriteLine( "myAL {0}.", myAL.IsFixedSize ? "has a fixed size" : "does not have a fixed size" );
      Console.WriteLine( "myFixedSizeAL {0}.", myFixedSizeAL.IsFixedSize ? "has a fixed size" : "does not have a fixed size" );
      Console.WriteLine();

      // Display both ArrayLists.
      Console.WriteLine( "Initially," );
      Console.Write( "Standard  :" );
      PrintValues( myAL, ' ' );
      Console.Write( "Fixed size:" );
      PrintValues( myFixedSizeAL, ' ' );

      // Sort is allowed in the fixed-size ArrayList.
      myFixedSizeAL.Sort();

      // Display both ArrayLists.
      Console.WriteLine( "After Sort," );
      Console.Write( "Standard  :" );
      PrintValues( myAL, ' ' );
      Console.Write( "Fixed size:" );
      PrintValues( myFixedSizeAL, ' ' );

      // Reverse is allowed in the fixed-size ArrayList.
      myFixedSizeAL.Reverse();

      // Display both ArrayLists.
      Console.WriteLine( "After Reverse," );
      Console.Write( "Standard  :" );
      PrintValues( myAL, ' ' );
      Console.Write( "Fixed size:" );
      PrintValues( myFixedSizeAL, ' ' );

      // Add an element to the standard ArrayList.
      myAL.Add( "AddMe" );

      // Display both ArrayLists.
      Console.WriteLine( "After adding to the standard ArrayList," );
      Console.Write( "Standard  :" );
      PrintValues( myAL, ' ' );
      Console.Write( "Fixed size:" );
      PrintValues( myFixedSizeAL, ' ' );
      Console.WriteLine();

      // Adding or inserting elements to the fixed-size ArrayList throws an exception.
      try  {
         myFixedSizeAL.Add( "AddMe2" );
      } catch ( Exception myException )  {
         Console.WriteLine("Exception: " + myException.ToString());
      }
      try  {
         myFixedSizeAL.Insert( 3, "InsertMe" );
      } catch ( Exception myException )  {
         Console.WriteLine("Exception: " + myException.ToString());
      }
   }

   public static void PrintValues( IEnumerable myList, char mySeparator )  {
      foreach ( Object obj in myList )
         Console.Write( "{0}{1}", mySeparator, obj );
      Console.WriteLine();
   }
}
/*
This code produces the following output.

myAL does not have a fixed size.
myFixedSizeAL has a fixed size.

Initially,
Standard  : The quick brown fox jumps over the lazy dog
Fixed size: The quick brown fox jumps over the lazy dog
After Sort,
Standard  : brown dog fox jumps lazy over quick the The
Fixed size: brown dog fox jumps lazy over quick the The
After Reverse,
Standard  : The the quick over lazy jumps fox dog brown
Fixed size: The the quick over lazy jumps fox dog brown
After adding to the standard ArrayList,
Standard  : The the quick over lazy jumps fox dog brown AddMe
Fixed size: The the quick over lazy jumps fox dog brown AddMe

Exception: System.NotSupportedException: Collection was of a fixed size.
   at System.Collections.FixedSizeArrayList.Add(Object obj)
   at SamplesArrayList.Main()
Exception: System.NotSupportedException: Collection was of a fixed size.
   at System.Collections.FixedSizeArrayList.Insert(int index, Object obj)
   at SamplesArrayList.Main()

*/

Imports System.Collections

Public Class SamplesArrayList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new ArrayList.
        Dim myAL As New ArrayList()
        myAL.Add("The")
        myAL.Add("quick")
        myAL.Add("brown")
        myAL.Add("fox")
        myAL.Add("jumps")
        myAL.Add("over")
        myAL.Add("the")
        myAL.Add("lazy")
        myAL.Add("dog")
        
        ' Create a fixed-size wrapper around the ArrayList.
        Dim myFixedSizeAL As ArrayList = ArrayList.FixedSize(myAL)
        
        ' Display whether the ArrayLists have a fixed size or not.
        Dim msg As String
        If myAL.IsFixedSize Then
            msg = "has a fixed size"
        Else
            msg = "does not have a fixed size"
        End If
        Console.WriteLine("myAL {0}.", msg)
        If myFixedSizeAL.IsFixedSize Then
            msg = "has a fixed size"
        Else
            msg = "does not have a fixed size"
        End If
        Console.WriteLine("myFixedSizeAL {0}.", msg)
        Console.WriteLine()
        
        ' Display both ArrayLists.
        Console.WriteLine("Initially,")
        Console.Write("Standard  :")
        PrintValues(myAL, " "c)
        Console.Write("Fixed size:")
        PrintValues(myFixedSizeAL, " "c)
        
        ' Sort is allowed in the fixed-size ArrayList.
        myFixedSizeAL.Sort()
        
        ' Display both ArrayLists.
        Console.WriteLine("After Sort,")
        Console.Write("Standard  :")
        PrintValues(myAL, " "c)
        Console.Write("Fixed size:")
        PrintValues(myFixedSizeAL, " "c)
        
        ' Reverse is allowed in the fixed-size ArrayList.
        myFixedSizeAL.Reverse()
        
        ' Display both ArrayLists.
        Console.WriteLine("After Reverse,")
        Console.Write("Standard  :")
        PrintValues(myAL, " "c)
        Console.Write("Fixed size:")
        PrintValues(myFixedSizeAL, " "c)
        
        ' Add an element to the standard ArrayList.
        myAL.Add("AddMe")
        
        ' Display both ArrayLists.
        Console.WriteLine("After adding to the standard ArrayList,")
        Console.Write("Standard  :")
        PrintValues(myAL, " "c)
        Console.Write("Fixed size:")
        PrintValues(myFixedSizeAL, " "c)
        Console.WriteLine()
        
        ' Adding or inserting elements to the fixed-size ArrayList throws an exception.
        Try
            myFixedSizeAL.Add("AddMe2")
        Catch myException As Exception
            Console.WriteLine("Exception: " + myException.ToString())
        End Try
        Try
            myFixedSizeAL.Insert(3, "InsertMe")
        Catch myException As Exception
            Console.WriteLine("Exception: " + myException.ToString())
        End Try
    End Sub

    Public Shared Sub PrintValues(myList As IEnumerable, mySeparator As Char)
        Dim obj As [Object]
        For Each obj In  myList
            Console.Write("{0}{1}", mySeparator, obj)
        Next obj
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' myAL does not have a fixed size.
' myFixedSizeAL has a fixed size.
' 
' Initially,
' Standard  : The quick brown fox jumps over the lazy dog
' Fixed size: The quick brown fox jumps over the lazy dog
' After Sort,
' Standard  : brown dog fox jumps lazy over quick the The
' Fixed size: brown dog fox jumps lazy over quick the The
' After Reverse,
' Standard  : The the quick over lazy jumps fox dog brown
' Fixed size: The the quick over lazy jumps fox dog brown
' After adding to the standard ArrayList,
' Standard  : The the quick over lazy jumps fox dog brown AddMe
' Fixed size: The the quick over lazy jumps fox dog brown AddMe
' 
' Exception: System.NotSupportedException: Collection was of a fixed size.
'    at System.Collections.FixedSizeArrayList.Add(Object obj)
'    at SamplesArrayList.Main()
' Exception: System.NotSupportedException: Collection was of a fixed size.
'    at System.Collections.FixedSizeArrayList.Insert(Int32 index, Object obj)
'    at SamplesArrayList.Main()

Комментарии

Эту оболочку можно использовать для предотвращения добавления и удаления исходного ArrayListобъекта . Элементы по-прежнему можно изменять или заменять.

Коллекция с фиксированным размером — это просто коллекция с оболочкой, которая предотвращает добавление и удаление элементов; Таким образом, если в базовую коллекцию вносятся изменения, включая добавление или удаление элементов, то коллекция фиксированного размера отражает эти изменения.

Этот метод является операцией O(1) .

Применяется к

FixedSize(IList)

Исходный код:
ArrayList.cs
Исходный код:
ArrayList.cs
Исходный код:
ArrayList.cs

Возвращает оболочку IList фиксированного размера.

public:
 static System::Collections::IList ^ FixedSize(System::Collections::IList ^ list);
public static System.Collections.IList FixedSize (System.Collections.IList list);
static member FixedSize : System.Collections.IList -> System.Collections.IList
Public Shared Function FixedSize (list As IList) As IList

Параметры

list
IList

Класс IList, для которого создается оболочка.

Возвращаемое значение

IList

Оболочка IList фиксированного размера.

Исключения

ArgumentNullException

list имеет значение null.

Комментарии

Эту оболочку можно использовать для предотвращения добавления и удаления исходного IListобъекта . Элементы по-прежнему можно изменять или заменять.

Коллекция с фиксированным размером — это просто коллекция с оболочкой, которая предотвращает добавление и удаление элементов; Таким образом, если в базовую коллекцию вносятся изменения, включая добавление или удаление элементов, то коллекция фиксированного размера отражает эти изменения.

Этот метод является операцией O(1) .

Применяется к