MemoryCache Class

Definition

Represents the type that implements an in-memory cache.

public ref class MemoryCache : System::Runtime::Caching::ObjectCache, IDisposable
public class MemoryCache : System.Runtime.Caching.ObjectCache, IDisposable
type MemoryCache = class
    inherit ObjectCache
    interface IEnumerable
    interface IDisposable
Public Class MemoryCache
Inherits ObjectCache
Implements IDisposable
Inheritance
MemoryCache
Implements

Examples

The following example declares a reference to the default memory cache instance. The cache entry uses a CacheItemPolicy object to provide eviction and expiration details for the cache entry. It also uses a ChangeMonitor object to monitor the state of the source data (which is a file) on the file system.

Private Sub btnGet_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim cache As ObjectCache = MemoryCache.[Default]
    Dim fileContents As String = TryCast(cache("filecontents"), String)

    If fileContents Is Nothing Then
        Dim policy As New CacheItemPolicy()
        Dim filePaths As New List(Of String)()
        filePaths.Add("c:\cache\example.txt")

        policy.ChangeMonitors.Add(New HostFileChangeMonitor(filePaths))

        ' Fetch the file contents.
        fileContents = File.ReadAllText("c:\cache\example.txt")

        cache.[Set]("filecontents", fileContents, policy)
    End If

    Label1.Text = fileContents
End Sub
private void btnGet_Click(object sender, EventArgs e)
{
    ObjectCache cache = MemoryCache.Default;
    string fileContents = cache["filecontents"] as string;

    if (fileContents == null)
    {
        CacheItemPolicy policy = new CacheItemPolicy();

        List<string> filePaths = new List<string>();
        filePaths.Add("c:\\cache\\example.txt");

        policy.ChangeMonitors.Add(new
        HostFileChangeMonitor(filePaths));

        // Fetch the file contents.
        fileContents =
            File.ReadAllText("c:\\cache\\example.txt");

        cache.Set("filecontents", fileContents, policy);
    }

    Label1.Text = fileContents;
}

Remarks

The MemoryCache class is a concrete implementation of the abstract ObjectCache class.

Note

The MemoryCache class is similar to the ASP.NET Cache class. The MemoryCache class has many properties and methods for accessing the cache that will be familiar to you if you have used the ASP.NET Cache class. The main differences between the Cache and MemoryCache classes are that the MemoryCache class has been changed to make it usable by .NET Framework applications that are not ASP.NET applications. For example, the MemoryCache class has no dependencies on the System.Web assembly. Another difference is that you can create multiple instances of the MemoryCache class for use in the same application and in the same AppDomain instance.

The MemoryCache class does not allow null as a value in the cache. Any attempt to add or change a cache entry with a value of null will fail.

The MemoryCache type does not implement cache regions. Therefore, when you call MemoryCache methods that implement base methods that contain a parameter for regions, do not pass a value for the parameter. The methods that use the region parameter all supply a default null value. For example, the MemoryCache.AddOrGetExisting method overload has a regionName parameter whose default value is null.

Constructors

MemoryCache(String, NameValueCollection)

Initializes a new instance of the MemoryCache class.

MemoryCache(String, NameValueCollection, Boolean)

Initializes a new instance of the MemoryCache class.

Properties

CacheMemoryLimit

Gets the amount of memory on the computer, in bytes, that can be used by the cache.

Default

Gets a reference to the default MemoryCache instance.

DefaultCacheCapabilities

Gets a description of the features that the cache provides.

Item[String]

Gets or sets a value in the cache by using the default indexer property for an instance of the MemoryCache class.

Name

Gets the name of the cache.

PhysicalMemoryLimit

Gets the percentage of physical memory that the cache can use.

PollingInterval

Gets the maximum time after which the cache updates its memory statistics.

Methods

Add(CacheItem, CacheItemPolicy)

Inserts a cache entry into the cache as a CacheItem instance, and adds details about how the entry should be evicted.

Add(CacheItem, CacheItemPolicy)

When overridden in a derived class, tries to insert a cache entry into the cache as a CacheItem instance, and adds details about how the entry should be evicted.

(Inherited from ObjectCache)
Add(String, Object, CacheItemPolicy, String)

When overridden in a derived class, inserts a cache entry into the cache, specifying information about how the entry will be evicted.

(Inherited from ObjectCache)
Add(String, Object, DateTimeOffset, String)

When overridden in a derived class, inserts a cache entry into the cache without overwriting any existing cache entry.

(Inherited from ObjectCache)
AddOrGetExisting(CacheItem, CacheItemPolicy)

Adds a cache entry into the cache using the specified CacheItem instance and details about how to evict the entry.

AddOrGetExisting(String, Object, CacheItemPolicy, String)

Inserts a cache entry into the cache using the specified key and value and the specified details for how it is to be evicted.

AddOrGetExisting(String, Object, DateTimeOffset, String)

Adds a cache entry into the cache using the specified key and a value and an absolute expiration value.

Contains(String, String)

Determines whether a cache entry exists in the cache.

CreateCacheEntryChangeMonitor(IEnumerable<String>, String)

Creates a CacheEntryChangeMonitor object that can trigger events in response to changes to specified cache entries.

Dispose()

Releases all resources that are used by the current instance of the MemoryCache class.

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Get(String, String)

Returns an entry from the cache.

GetCacheItem(String, String)

Returns the specified entry from the cache as a CacheItem instance.

GetCount(String)

Returns the total number of cache entries in the cache.

GetEnumerator()

Creates an enumerator that can be used to iterate through a collection of cache entries.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetLastSize(String)

Gets the size of the named region.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
GetValues(IEnumerable<String>, String)

Returns a set of cache entries that correspond to the specified keys.

GetValues(String, String[])

Gets a set of cache entries that correspond to the specified keys.

(Inherited from ObjectCache)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
Remove(String, CacheEntryRemovedReason, String)

Removes a cache entry from the cache using the reason.

Remove(String, String)

Removes a cache entry from the cache.

Set(CacheItem, CacheItemPolicy)

Inserts a cache entry into the cache by using a CacheItem instance to supply the key and value for the cache entry.

Set(String, Object, CacheItemPolicy, String)

Inserts a cache entry into the cache by using a key and a value and eviction.

Set(String, Object, DateTimeOffset, String)

Inserts a cache entry into the cache by using a key and a value and specifies time-based expiration details.

ToString()

Returns a string that represents the current object.

(Inherited from Object)
Trim(Int32)

Removes a specified percentage of cache entries from the cache object.

Explicit Interface Implementations

IEnumerable.GetEnumerator()

Provides support for iteration over a generic collection.

IEnumerable<KeyValuePair<String,Object>>.GetEnumerator()

Supports iteration over a strongly typed collection.

(Inherited from ObjectCache)

Extension Methods

CopyToDataTable<T>(IEnumerable<T>)

Returns a DataTable that contains copies of the DataRow objects, given an input IEnumerable<T> object where the generic parameter T is DataRow.

CopyToDataTable<T>(IEnumerable<T>, DataTable, LoadOption)

Copies DataRow objects to the specified DataTable, given an input IEnumerable<T> object where the generic parameter T is DataRow.

CopyToDataTable<T>(IEnumerable<T>, DataTable, LoadOption, FillErrorEventHandler)

Copies DataRow objects to the specified DataTable, given an input IEnumerable<T> object where the generic parameter T is DataRow.

Aggregate<TSource>(IEnumerable<TSource>, Func<TSource,TSource,TSource>)

Applies an accumulator function over a sequence.

Aggregate<TSource,TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>)

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.

Aggregate<TSource,TAccumulate,TResult>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>, Func<TAccumulate,TResult>)

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value.

All<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Determines whether all elements of a sequence satisfy a condition.

Any<TSource>(IEnumerable<TSource>)

Determines whether a sequence contains any elements.

Any<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Determines whether any element of a sequence satisfies a condition.

Append<TSource>(IEnumerable<TSource>, TSource)

Appends a value to the end of the sequence.

AsEnumerable<TSource>(IEnumerable<TSource>)

Returns the input typed as IEnumerable<T>.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Computes the average of a sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Computes the average of a sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

Cast<TResult>(IEnumerable)

Casts the elements of an IEnumerable to the specified type.

Concat<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Concatenates two sequences.

Contains<TSource>(IEnumerable<TSource>, TSource)

Determines whether a sequence contains a specified element by using the default equality comparer.

Contains<TSource>(IEnumerable<TSource>, TSource, IEqualityComparer<TSource>)

Determines whether a sequence contains a specified element by using a specified IEqualityComparer<T>.

Count<TSource>(IEnumerable<TSource>)

Returns the number of elements in a sequence.

Count<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns a number that represents how many elements in the specified sequence satisfy a condition.

DefaultIfEmpty<TSource>(IEnumerable<TSource>)

Returns the elements of the specified sequence or the type parameter's default value in a singleton collection if the sequence is empty.

DefaultIfEmpty<TSource>(IEnumerable<TSource>, TSource)

Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty.

Distinct<TSource>(IEnumerable<TSource>)

Returns distinct elements from a sequence by using the default equality comparer to compare values.

Distinct<TSource>(IEnumerable<TSource>, IEqualityComparer<TSource>)

Returns distinct elements from a sequence by using a specified IEqualityComparer<T> to compare values.

ElementAt<TSource>(IEnumerable<TSource>, Int32)

Returns the element at a specified index in a sequence.

ElementAtOrDefault<TSource>(IEnumerable<TSource>, Int32)

Returns the element at a specified index in a sequence or a default value if the index is out of range.

Except<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set difference of two sequences by using the default equality comparer to compare values.

Except<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set difference of two sequences by using the specified IEqualityComparer<T> to compare values.

First<TSource>(IEnumerable<TSource>)

Returns the first element of a sequence.

First<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the first element in a sequence that satisfies a specified condition.

FirstOrDefault<TSource>(IEnumerable<TSource>)

Returns the first element of a sequence, or a default value if the sequence contains no elements.

FirstOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

GroupBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Groups the elements of a sequence according to a specified key selector function.

GroupBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Groups the elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer.

GroupBy<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Groups the elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function.

GroupBy<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Groups the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

GroupBy<TSource,TKey,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>)

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.

GroupBy<TSource,TKey,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>, IEqualityComparer<TKey>)

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The keys are compared by using a specified comparer.

GroupBy<TSource,TKey,TElement,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>,TResult>)

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function.

GroupBy<TSource,TKey,TElement,TResult>(IEnumerable<TSource>, Func<TSource, TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function.

GroupJoin<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,IEnumerable<TInner>, TResult>)

Correlates the elements of two sequences based on equality of keys and groups the results. The default equality comparer is used to compare keys.

GroupJoin<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,IEnumerable<TInner>, TResult>, IEqualityComparer<TKey>)

Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparer<T> is used to compare keys.

Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set intersection of two sequences by using the default equality comparer to compare values.

Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.

Join<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,TInner,TResult>)

Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys.

Join<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,TInner,TResult>, IEqualityComparer<TKey>)

Correlates the elements of two sequences based on matching keys. A specified IEqualityComparer<T> is used to compare keys.

Last<TSource>(IEnumerable<TSource>)

Returns the last element of a sequence.

Last<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the last element of a sequence that satisfies a specified condition.

LastOrDefault<TSource>(IEnumerable<TSource>)

Returns the last element of a sequence, or a default value if the sequence contains no elements.

LastOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.

LongCount<TSource>(IEnumerable<TSource>)

Returns an Int64 that represents the total number of elements in a sequence.

LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns an Int64 that represents how many elements in a sequence satisfy a condition.

Max<TSource>(IEnumerable<TSource>)

Returns the maximum value in a generic sequence.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Invokes a transform function on each element of a sequence and returns the maximum Decimal value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Invokes a transform function on each element of a sequence and returns the maximum Double value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Invokes a transform function on each element of a sequence and returns the maximum Int32 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Invokes a transform function on each element of a sequence and returns the maximum Int64 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Decimal value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Double value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Int64 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Single value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Invokes a transform function on each element of a sequence and returns the maximum Single value.

Max<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Invokes a transform function on each element of a generic sequence and returns the maximum resulting value.

Min<TSource>(IEnumerable<TSource>)

Returns the minimum value in a generic sequence.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Invokes a transform function on each element of a sequence and returns the minimum Decimal value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Invokes a transform function on each element of a sequence and returns the minimum Double value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Invokes a transform function on each element of a sequence and returns the minimum Int32 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Invokes a transform function on each element of a sequence and returns the minimum Int64 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Double value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Int32 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Int64 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Single value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Invokes a transform function on each element of a sequence and returns the minimum Single value.

Min<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Invokes a transform function on each element of a generic sequence and returns the minimum resulting value.

OfType<TResult>(IEnumerable)

Filters the elements of an IEnumerable based on a specified type.

OrderBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Sorts the elements of a sequence in ascending order according to a key.

OrderBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Sorts the elements of a sequence in ascending order by using a specified comparer.

OrderByDescending<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Sorts the elements of a sequence in descending order according to a key.

OrderByDescending<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Sorts the elements of a sequence in descending order by using a specified comparer.

Prepend<TSource>(IEnumerable<TSource>, TSource)

Adds a value to the beginning of the sequence.

Reverse<TSource>(IEnumerable<TSource>)

Inverts the order of the elements in a sequence.

Select<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Projects each element of a sequence into a new form.

Select<TSource,TResult>(IEnumerable<TSource>, Func<TSource,Int32,TResult>)

Projects each element of a sequence into a new form by incorporating the element's index.

SelectMany<TSource,TResult>(IEnumerable<TSource>, Func<TSource,IEnumerable<TResult>>)

Projects each element of a sequence to an IEnumerable<T> and flattens the resulting sequences into one sequence.

SelectMany<TSource,TResult>(IEnumerable<TSource>, Func<TSource,Int32,IEnumerable<TResult>>)

Projects each element of a sequence to an IEnumerable<T>, and flattens the resulting sequences into one sequence. The index of each source element is used in the projected form of that element.

SelectMany<TSource,TCollection,TResult>(IEnumerable<TSource>, Func<TSource,IEnumerable<TCollection>>, Func<TSource,TCollection,TResult>)

Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein.

SelectMany<TSource,TCollection,TResult>(IEnumerable<TSource>, Func<TSource,Int32,IEnumerable<TCollection>>, Func<TSource,TCollection,TResult>)

Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. The index of each source element is used in the intermediate projected form of that element.

SequenceEqual<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Determines whether two sequences are equal by comparing the elements by using the default equality comparer for their type.

SequenceEqual<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Determines whether two sequences are equal by comparing their elements by using a specified IEqualityComparer<T>.

Single<TSource>(IEnumerable<TSource>)

Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.

Single<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

SingleOrDefault<TSource>(IEnumerable<TSource>)

Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.

SingleOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the only element of a sequence that satisfies a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the condition.

Skip<TSource>(IEnumerable<TSource>, Int32)

Bypasses a specified number of elements in a sequence and then returns the remaining elements.

SkipWhile<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.

SkipWhile<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the sum of the sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the sum of the sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the sum of the sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the sum of the sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Computes the sum of the sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Computes the sum of the sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Computes the sum of the sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Computes the sum of the sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Computes the sum of the sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the sum of the sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

Take<TSource>(IEnumerable<TSource>, Int32)

Returns a specified number of contiguous elements from the start of a sequence.

TakeWhile<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns elements from a sequence as long as a specified condition is true.

TakeWhile<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

Returns elements from a sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function.

ToArray<TSource>(IEnumerable<TSource>)

Creates an array from a IEnumerable<T>.

ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function.

ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function and key comparer.

ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to specified key selector and element selector functions.

ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function, a comparer, and an element selector function.

ToHashSet<TSource>(IEnumerable<TSource>)

Creates a HashSet<T> from an IEnumerable<T>.

ToHashSet<TSource>(IEnumerable<TSource>, IEqualityComparer<TSource>)

Creates a HashSet<T> from an IEnumerable<T> using the comparer to compare keys.

ToList<TSource>(IEnumerable<TSource>)

Creates a List<T> from an IEnumerable<T>.

ToLookup<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function.

ToLookup<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function and key comparer.

ToLookup<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to specified key selector and element selector functions.

ToLookup<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function, a comparer and an element selector function.

Union<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set union of two sequences by using the default equality comparer.

Union<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set union of two sequences by using a specified IEqualityComparer<T>.

Where<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Filters a sequence of values based on a predicate.

Where<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function.

Zip<TFirst,TSecond,TResult>(IEnumerable<TFirst>, IEnumerable<TSecond>, Func<TFirst,TSecond,TResult>)

Applies a specified function to the corresponding elements of two sequences, producing a sequence of the results.

AsParallel(IEnumerable)

Enables parallelization of a query.

AsParallel<TSource>(IEnumerable<TSource>)

Enables parallelization of a query.

AsQueryable(IEnumerable)

Converts an IEnumerable to an IQueryable.

AsQueryable<TElement>(IEnumerable<TElement>)

Converts a generic IEnumerable<T> to a generic IQueryable<T>.

Ancestors<T>(IEnumerable<T>)

Returns a collection of elements that contains the ancestors of every node in the source collection.

Ancestors<T>(IEnumerable<T>, XName)

Returns a filtered collection of elements that contains the ancestors of every node in the source collection. Only elements that have a matching XName are included in the collection.

DescendantNodes<T>(IEnumerable<T>)

Returns a collection of the descendant nodes of every document and element in the source collection.

Descendants<T>(IEnumerable<T>)

Returns a collection of elements that contains the descendant elements of every element and document in the source collection.

Descendants<T>(IEnumerable<T>, XName)

Returns a filtered collection of elements that contains the descendant elements of every element and document in the source collection. Only elements that have a matching XName are included in the collection.

Elements<T>(IEnumerable<T>)

Returns a collection of the child elements of every element and document in the source collection.

Elements<T>(IEnumerable<T>, XName)

Returns a filtered collection of the child elements of every element and document in the source collection. Only elements that have a matching XName are included in the collection.

InDocumentOrder<T>(IEnumerable<T>)

Returns a collection of nodes that contains all nodes in the source collection, sorted in document order.

Nodes<T>(IEnumerable<T>)

Returns a collection of the child nodes of every document and element in the source collection.

Remove<T>(IEnumerable<T>)

Removes every node in the source collection from its parent node.

Applies to

Thread Safety

This type is thread safe.

See also