ArrayList.Contains(Object) Method

Reference

Definition

Namespace:: System.Collections

Assemblies:: mscorlib.dll, System.Collections.NonGeneric.dll

Assembly:: System.Runtime.dll

Assembly:: System.Collections.NonGeneric.dll

Assembly:: System.Runtime.Extensions.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: ArrayList.cs

Source:: ArrayList.cs

Source:: ArrayList.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Determines whether an element is in the ArrayList.

public:
 virtual bool Contains(System::Object ^ item);

public virtual bool Contains (object item);

public virtual bool Contains (object? item);

abstract member Contains : obj -> bool
override this.Contains : obj -> bool

Public Overridable Function Contains (item As Object) As Boolean

Parameters

item: Object

The Object to locate in the ArrayList. The value can be null.

Returns

Boolean

true if item is found in the ArrayList; otherwise, false.

Implements

Contains(Object)

Remarks

This method performs a linear search; therefore, this method is an O(n) operation, where n is Count.

This method determines equality by calling Object.Equals.

Starting with the .NET Framework 2.0, this method uses the collection's objects' Equals and CompareTo methods on item to determine whether item exists. In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.

Applies to

Share via