Export (0) Print
Expand All
20 out of 28 rated this helpful - Rate this topic

ArrayList Class

Implements the IList interface using an array whose size is dynamically increased as required.

To browse the .NET Framework source code for this type, see the Reference Source.

Namespace:  System.Collections
Assembly:  mscorlib (in mscorlib.dll)
[SerializableAttribute]
[ComVisibleAttribute(true)]
public class ArrayList : IList, ICollection, 
	IEnumerable, ICloneable

The ArrayList type exposes the following members.

  NameDescription
Public methodSupported by the XNA FrameworkArrayList()Initializes a new instance of the ArrayList class that is empty and has the default initial capacity.
Public methodSupported by the XNA FrameworkArrayList(ICollection)Initializes a new instance of the ArrayList class that contains elements copied from the specified collection and that has the same initial capacity as the number of elements copied.
Public methodSupported by the XNA FrameworkArrayList(Int32)Initializes a new instance of the ArrayList class that is empty and has the specified initial capacity.
Top
  NameDescription
Public propertySupported by the XNA FrameworkCapacityGets or sets the number of elements that the ArrayList can contain.
Public propertySupported by the XNA FrameworkCountGets the number of elements actually contained in the ArrayList.
Public propertySupported by the XNA FrameworkIsFixedSizeGets a value indicating whether the ArrayList has a fixed size.
Public propertySupported by the XNA FrameworkIsReadOnlyGets a value indicating whether the ArrayList is read-only.
Public propertySupported by the XNA FrameworkIsSynchronizedGets a value indicating whether access to the ArrayList is synchronized (thread safe).
Public propertySupported by the XNA FrameworkItemGets or sets the element at the specified index.
Public propertySupported by the XNA FrameworkSyncRootGets an object that can be used to synchronize access to the ArrayList.
Top
  NameDescription
Public methodStatic memberAdapterCreates an ArrayList wrapper for a specific IList.
Public methodSupported by the XNA FrameworkAddAdds an object to the end of the ArrayList.
Public methodSupported by the XNA FrameworkAddRangeAdds the elements of an ICollection to the end of the ArrayList.
Public methodBinarySearch(Object)Searches the entire sorted ArrayList for an element using the default comparer and returns the zero-based index of the element.
Public methodBinarySearch(Object, IComparer)Searches the entire sorted ArrayList for an element using the specified comparer and returns the zero-based index of the element.
Public methodSupported by the XNA FrameworkBinarySearch(Int32, Int32, Object, IComparer)Searches a range of elements in the sorted ArrayList for an element using the specified comparer and returns the zero-based index of the element.
Public methodSupported by the XNA FrameworkClearRemoves all elements from the ArrayList.
Public methodSupported by the XNA FrameworkCloneCreates a shallow copy of the ArrayList.
Public methodSupported by the XNA FrameworkContainsDetermines whether an element is in the ArrayList.
Public methodSupported by the XNA FrameworkCopyTo(Array)Copies the entire ArrayList to a compatible one-dimensional Array, starting at the beginning of the target array.
Public methodSupported by the XNA FrameworkCopyTo(Array, Int32)Copies the entire ArrayList to a compatible one-dimensional Array, starting at the specified index of the target array.
Public methodSupported by the XNA FrameworkCopyTo(Int32, Array, Int32, Int32)Copies a range of elements from the ArrayList to a compatible one-dimensional Array, starting at the specified index of the target array.
Public methodSupported by the XNA FrameworkEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodSupported by the XNA FrameworkFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodStatic memberFixedSize(ArrayList)Returns an ArrayList wrapper with a fixed size.
Public methodStatic memberFixedSize(IList)Returns an IList wrapper with a fixed size.
Public methodSupported by the XNA FrameworkGetEnumerator()Returns an enumerator for the entire ArrayList.
Public methodGetEnumerator(Int32, Int32)Returns an enumerator for a range of elements in the ArrayList.
Public methodSupported by the XNA FrameworkGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetRangeReturns an ArrayList which represents a subset of the elements in the source ArrayList.
Public methodSupported by the XNA FrameworkGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodSupported by the XNA FrameworkIndexOf(Object)Searches for the specified Object and returns the zero-based index of the first occurrence within the entire ArrayList.
Public methodIndexOf(Object, Int32)Searches for the specified Object and returns the zero-based index of the first occurrence within the range of elements in the ArrayList that extends from the specified index to the last element.
Public methodSupported by the XNA FrameworkIndexOf(Object, Int32, Int32)Searches for the specified Object and returns the zero-based index of the first occurrence within the range of elements in the ArrayList that starts at the specified index and contains the specified number of elements.
Public methodSupported by the XNA FrameworkInsertInserts an element into the ArrayList at the specified index.
Public methodSupported by the XNA FrameworkInsertRangeInserts the elements of a collection into the ArrayList at the specified index.
Public methodLastIndexOf(Object)Searches for the specified Object and returns the zero-based index of the last occurrence within the entire ArrayList.
Public methodLastIndexOf(Object, Int32)Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that extends from the first element to the specified index.
Public methodLastIndexOf(Object, Int32, Int32)Searches for the specified Object and returns the zero-based index of the last occurrence within the range of elements in the ArrayList that contains the specified number of elements and ends at the specified index.
Protected methodSupported by the XNA FrameworkMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodStatic memberReadOnly(ArrayList)Returns a read-only ArrayList wrapper.
Public methodStatic memberReadOnly(IList)Returns a read-only IList wrapper.
Public methodSupported by the XNA FrameworkRemoveRemoves the first occurrence of a specific object from the ArrayList.
Public methodSupported by the XNA FrameworkRemoveAtRemoves the element at the specified index of the ArrayList.
Public methodSupported by the XNA FrameworkRemoveRangeRemoves a range of elements from the ArrayList.
Public methodStatic memberRepeatReturns an ArrayList whose elements are copies of the specified value.
Public methodSupported by the XNA FrameworkReverse()Reverses the order of the elements in the entire ArrayList.
Public methodSupported by the XNA FrameworkReverse(Int32, Int32)Reverses the order of the elements in the specified range.
Public methodSetRangeCopies the elements of a collection over a range of elements in the ArrayList.
Public methodSupported by the XNA FrameworkSort()Sorts the elements in the entire ArrayList.
Public methodSupported by the XNA FrameworkSort(IComparer)Sorts the elements in the entire ArrayList using the specified comparer.
Public methodSupported by the XNA FrameworkSort(Int32, Int32, IComparer)Sorts the elements in a range of elements in ArrayList using the specified comparer.
Public methodStatic memberSupported by the XNA FrameworkSynchronized(ArrayList)Returns an ArrayList wrapper that is synchronized (thread safe).
Public methodStatic memberSynchronized(IList)Returns an IList wrapper that is synchronized (thread safe).
Public methodSupported by the XNA FrameworkToArray()Copies the elements of the ArrayList to a new Object array.
Public methodSupported by the XNA FrameworkToArray(Type)Copies the elements of the ArrayList to a new array of the specified element type.
Public methodSupported by the XNA FrameworkToStringReturns a string that represents the current object. (Inherited from Object.)
Public methodSupported by the XNA FrameworkTrimToSizeSets the capacity to the actual number of elements in the ArrayList.
Top
  NameDescription
Public Extension MethodAsParallelEnables parallelization of a query. (Defined by ParallelEnumerable.)
Public Extension MethodAsQueryableConverts an IEnumerable to an IQueryable. (Defined by Queryable.)
Public Extension MethodSupported by the XNA FrameworkCast<TResult>Casts the elements of an IEnumerable to the specified type. (Defined by Enumerable.)
Public Extension MethodSupported by the XNA FrameworkOfType<TResult>Filters the elements of an IEnumerable based on a specified type. (Defined by Enumerable.)
Top
NoteNote

To view the .NET Framework source code for this type, see the Reference Source. You can browse through the source code online, download the reference for offline viewing, and step through the sources (including patches and updates) during debugging; see instructions.

For a strongly-typed alternative to ArrayList, consider using List<T>. ArrayList may not always offer the best performance for a given task. See the "Performance Considerations" section in the List<T> reference topic for a discussion of the relative performance of these classes.

The ArrayList is not guaranteed to be sorted. You must sort the ArrayList prior to performing operations (such as BinarySearch) that require the ArrayList to be sorted.

The capacity of an ArrayList is the number of elements the ArrayList can hold. As elements are added to an ArrayList, the capacity is automatically increased as required through reallocation. The capacity can be decreased by calling TrimToSize or by setting the Capacity property explicitly.

For very large ArrayList objects, you can increase the maximum capacity to 2 billion elements on a 64-bit system by setting the enabled attribute of the gcAllowVeryLargeObjects configuration element to true in the run-time environment.

Elements in this collection can be accessed using an integer index. Indexes in this collection are zero-based.

The ArrayList collection accepts null as a valid value, allows duplicate elements.

Using multidimensional arrays as elements in an ArrayList collection is not supported.

The following code example shows how to create and initialize an ArrayList and how to print out its values.

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

   public static void Main()  {

      // Creates and initializes a new ArrayList.
      ArrayList myAL = new ArrayList();
      myAL.Add("Hello");
      myAL.Add("World");
      myAL.Add("!");

      // Displays the properties and values of the ArrayList.
      Console.WriteLine( "myAL" );
      Console.WriteLine( "    Count:    {0}", myAL.Count );
      Console.WriteLine( "    Capacity: {0}", myAL.Capacity );
      Console.Write( "    Values:" );
      PrintValues( myAL );
   }

   public static void PrintValues( IEnumerable myList )  {
      foreach ( Object obj in myList )
         Console.Write( "   {0}", obj );
      Console.WriteLine();
   }

}


/* 
This code produces output similar to the following:

myAL
    Count:    3
    Capacity: 4
    Values:   Hello   World   !

*/

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

An ArrayList can support multiple readers concurrently, as long as the collection is not modified. To guarantee the thread safety of the ArrayList, all operations must be done through the wrapper returned by the Synchronized method.

Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads can still modify the collection, which causes the enumerator to throw an exception. To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.

Did you find this helpful?
(1500 characters remaining)
Thank you for your feedback
Show:
© 2014 Microsoft. All rights reserved.