HashSet(Of T).Overlaps Method (IEnumerable(Of T))
.NET Framework (current version)
Determines whether the current HashSet(Of T) object and a specified collection share common elements.
Assembly: System.Core (in System.Core.dll)
Parameters
- other
-
Type:
System.Collections.Generic.IEnumerable(Of T)
The collection to compare to the current HashSet(Of T) object.
Return Value
Type: System.Booleantrue if the HashSet(Of T) object and other share at least one common element; otherwise, false.
Implements
ISet(Of T).Overlaps(IEnumerable(Of T))| Exception | Condition |
|---|---|
| ArgumentNullException | other is null. |
This method is an O(n) operation, where n is the number of elements in other.
The following example creates two disparate HashSet(Of T) objects and compares them to each another. In this example, allNumbers and lowNumbers are shown to share common elements using the Overlaps method.
Shared Sub Main() Dim lowNumbers As HashSet(Of Integer) = New HashSet(Of Integer)() Dim allNumbers As HashSet(Of Integer) = New HashSet(Of Integer)() For i As Integer = 1 To 4 lowNumbers.Add(i) Next i For i As Integer = 0 To 9 allNumbers.Add(i) Next i Console.Write("lowNumbers contains {0} elements: ", lowNumbers.Count) DisplaySet(lowNumbers) Console.Write("allNumbers contains {0} elements: ", allNumbers.Count) DisplaySet(allNumbers) Console.WriteLine("lowNumbers overlaps allNumbers: {0}", _ lowNumbers.Overlaps(allNumbers)) Console.WriteLine("allNumbers and lowNumbers are equal sets: {0}", _ allNumbers.SetEquals(lowNumbers)) ' Show the results of sub/superset testing Console.WriteLine("lowNumbers is a subset of allNumbers: {0}", _ lowNumbers.IsSubsetOf(allNumbers)) Console.WriteLine("allNumbers is a superset of lowNumbers: {0}", _ allNumbers.IsSupersetOf(lowNumbers)) Console.WriteLine("lowNumbers is a proper subset of allNumbers: {0}", _ lowNumbers.IsProperSubsetOf(allNumbers)) Console.WriteLine("allNumbers is a proper superset of lowNumbers: {0}", _ allNumbers.IsProperSupersetOf(lowNumbers)) ' Modify allNumbers to remove numbers that are not in lowNumbers. allNumbers.IntersectWith(lowNumbers) Console.Write("allNumbers contains {0} elements: ", allNumbers.Count) DisplaySet(allNumbers) Console.WriteLine("allNumbers and lowNumbers are equal sets: {0}", _ allNumbers.SetEquals(lowNumbers)) ' Show the results of sub/superset testing with the modified set. Console.WriteLine("lowNumbers is a subset of allNumbers: {0}", _ lowNumbers.IsSubsetOf(allNumbers)) Console.WriteLine("allNumbers is a superset of lowNumbers: {0}", _ allNumbers.IsSupersetOf(lowNumbers)) Console.WriteLine("lowNumbers is a proper subset of allNumbers: {0}", _ lowNumbers.IsProperSubsetOf(allNumbers)) Console.WriteLine("allNumbers is a proper superset of lowNumbers: {0}", _ allNumbers.IsProperSupersetOf(lowNumbers)) End Sub ' This code example produces output similar to the following: ' lowNumbers contains 4 elements: { 1 2 3 4 } ' allNumbers contains 10 elements: { 0 1 2 3 4 5 6 7 8 9 } ' lowNumbers overlaps allNumbers: True ' allNumbers and lowNumbers are equal sets: False ' lowNumbers is a subset of allNumbers: True ' allNumbers is a superset of lowNumbers: True ' lowNumbers is a proper subset of allNumbers: True ' allNumbers is a proper superset of lowNumbers: True ' allNumbers contains 4 elements: { 1 2 3 4 } ' allNumbers and lowNumbers are equal sets: True ' lowNumbers is a subset of allNumbers: True ' allNumbers is a superset of lowNumbers: True ' lowNumbers is a proper subset of allNumbers: False ' allNumbers is a proper superset of lowNumbers: False
Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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