Enumerable.Count<'TSource> Method (IEnumerable<'TSource>)
Returns the number of elements in a sequence.
Assembly: System.Core (in System.Core.dll)
A sequence that contains elements to be counted.
Return ValueType: System.Int32
The number of elements in the input sequence.
The type of the elements of source.
If the type of source implements ICollection<'T>, that implementation is used to obtain the count of elements. Otherwise, this method determines the count.
In Visual Basic query expression syntax, an Aggregate Into Count() clause translates to an invocation of Count.
Available since 4.5
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Available since 8.1