BlockingCollection<T>.TryTake Method
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Tries to remove an item from the BlockingCollection<T>.
TryTake(T) |
Tries to remove an item from the BlockingCollection<T>. |
TryTake(T, TimeSpan) |
Tries to remove an item from the BlockingCollection<T> in the specified time period. |
TryTake(T, Int32, CancellationToken) |
Tries to remove an item from the BlockingCollection<T> in the specified time period while observing a cancellation token. |
TryTake(T, Int32) |
Tries to remove an item from the BlockingCollection<T> in the specified time period. |
The following example shows how to use the TryTake method.
class TryTakeDemo
{
// Demonstrates:
// BlockingCollection<T>.Add()
// BlockingCollection<T>.CompleteAdding()
// BlockingCollection<T>.TryTake()
// BlockingCollection<T>.IsCompleted
public static void BC_TryTake()
{
// Construct and fill our BlockingCollection
using (BlockingCollection<int> bc = new BlockingCollection<int>())
{
int NUMITEMS = 10000;
for (int i = 0; i < NUMITEMS; i++) bc.Add(i);
bc.CompleteAdding();
int outerSum = 0;
// Delegate for consuming the BlockingCollection and adding up all items
Action action = () =>
{
int localItem;
int localSum = 0;
while (bc.TryTake(out localItem)) localSum += localItem;
Interlocked.Add(ref outerSum, localSum);
};
// Launch three parallel actions to consume the BlockingCollection
Parallel.Invoke(action, action, action);
Console.WriteLine("Sum[0..{0}) = {1}, should be {2}", NUMITEMS, outerSum, ((NUMITEMS * (NUMITEMS - 1)) / 2));
Console.WriteLine("bc.IsCompleted = {0} (should be true)", bc.IsCompleted);
}
}
}
module TryTakeDemo =
// Demonstrates:
// BlockingCollection<T>.Add()
// BlockingCollection<T>.CompleteAdding()
// BlockingCollection<T>.TryTake()
// BlockingCollection<T>.IsCompleted
let blockingCollectionTryTake () =
// Construct and fill our BlockingCollection
use bc = new BlockingCollection<int>()
let NUMITEMS = 10000;
for i = 0 to NUMITEMS - 1 do
bc.Add i
bc.CompleteAdding()
let mutable outerSum = 0
// Delegate for consuming the BlockingCollection and adding up all items
let action =
Action(fun () ->
let mutable localItem = 0
let mutable localSum = 0
while bc.TryTake &localItem do
localSum <- localSum + localItem
Interlocked.Add(&outerSum, localSum)
|> ignore)
// Launch three parallel actions to consume the BlockingCollection
Parallel.Invoke(action, action, action)
printfn $"Sum[0..{NUMITEMS}) = {outerSum}, should be {((NUMITEMS * (NUMITEMS - 1)) / 2)}"
printfn $"bc.IsCompleted = {bc.IsCompleted} (should be true)"
'Imports System.Collections.Concurrent
'Imports System.Threading
'Imports System.Threading.Tasks
Class TryTakeDemo
' Demonstrates:
' BlockingCollection<T>.Add()
' BlockingCollection<T>.CompleteAdding()
' BlockingCollection<T>.TryTake()
' BlockingCollection<T>.IsCompleted
Shared Sub BC_TryTake()
' Construct and fill our BlockingCollection
Using bc As New BlockingCollection(Of Integer)()
Dim NUMITEMS As Integer = 10000
For i As Integer = 0 To NUMITEMS - 1
bc.Add(i)
Next
bc.CompleteAdding()
Dim outerSum As Integer = 0
' Delegate for consuming the BlockingCollection and adding up all items
Dim action As Action =
Sub()
Dim localItem As Integer
Dim localSum As Integer = 0
While bc.TryTake(localItem)
localSum += localItem
End While
Interlocked.Add(outerSum, localSum)
End Sub
' Launch three parallel actions to consume the BlockingCollection
Parallel.Invoke(action, action, action)
Console.WriteLine("Sum[0..{0}) = {1}, should be {2}", NUMITEMS, outerSum, ((NUMITEMS * (NUMITEMS - 1)) / 2))
Console.WriteLine("bc.IsCompleted = {0} (should be true)", bc.IsCompleted)
End Using
End Sub
End Class
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
Tries to remove an item from the BlockingCollection<T>.
public:
bool TryTake([Runtime::InteropServices::Out] T % item);
public bool TryTake (out T item);
member this.TryTake : 'T -> bool
Public Function TryTake (ByRef item As T) As Boolean
Parameters
- item
- T
The item to be removed from the collection.
Returns
true
if an item could be removed; otherwise, false
.
Exceptions
The BlockingCollection<T> has been disposed.
The underlying collection was modified outside of this BlockingCollection<T> instance.
Remarks
If the collection is empty, this method immediately returns false.
The order in which an item is removed depends on the type of collection used to create the BlockingCollection<T> instance. When you create a BlockingCollection<T> object, you can specify the type of collection to use. For example, you could specify a ConcurrentQueue<T> object for first in, first out (FIFO) behavior, or a ConcurrentStack<T> object for last in, first out (LIFO) behavior. You can use any collection class that implements the IProducerConsumerCollection<T> interface. The default collection type for BlockingCollection<T> is ConcurrentQueue<T>.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1 |
UWP | 10.0 |
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
Tries to remove an item from the BlockingCollection<T> in the specified time period.
public:
bool TryTake([Runtime::InteropServices::Out] T % item, TimeSpan timeout);
public bool TryTake (out T item, TimeSpan timeout);
member this.TryTake : 'T * TimeSpan -> bool
Public Function TryTake (ByRef item As T, timeout As TimeSpan) As Boolean
Parameters
- item
- T
The item to be removed from the collection.
- timeout
- TimeSpan
A TimeSpan that represents the number of milliseconds to wait for the item to be removed, or a TimeSpan that represents -1 milliseconds to wait indefinitely.
Returns
true
if an item could be removed from the collection within the specified time; otherwise, false
.
Exceptions
The BlockingCollection<T> has been disposed.
timeout
is a negative number other than -1 milliseconds, which represents an infinite time-out.
-or-
timeout
is greater than Int32.MaxValue.
The underlying collection was modified outside of this BlockingCollection<T> instance.
Remarks
The order in which an item is removed depends on the type of collection used to create the BlockingCollection<T> instance. When you create a BlockingCollection<T> object, you can specify the type of collection to use. For example, you could specify a ConcurrentQueue<T> object for first in, first out (FIFO) behavior, or a ConcurrentStack<T> object for last in, first out (LIFO) behavior. You can use any collection class that implements the IProducerConsumerCollection<T> interface. The default collection type for BlockingCollection<T> is ConcurrentQueue<T>.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1 |
UWP | 10.0 |
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
Tries to remove an item from the BlockingCollection<T> in the specified time period while observing a cancellation token.
public:
bool TryTake([Runtime::InteropServices::Out] T % item, int millisecondsTimeout, System::Threading::CancellationToken cancellationToken);
public bool TryTake (out T item, int millisecondsTimeout, System.Threading.CancellationToken cancellationToken);
member this.TryTake : 'T * int * System.Threading.CancellationToken -> bool
Public Function TryTake (ByRef item As T, millisecondsTimeout As Integer, cancellationToken As CancellationToken) As Boolean
Parameters
- item
- T
The item to be removed from the collection.
- millisecondsTimeout
- Int32
The number of milliseconds to wait for the item to be removed, or Infinite (-1) to wait indefinitely.
- cancellationToken
- CancellationToken
A cancellation token to observe.
Returns
true
if an item could be removed from the collection within the specified time; otherwise, false
.
Exceptions
The CancellationToken has been canceled.
The BlockingCollection<T> has been disposed or the underlying CancellationTokenSource has been disposed.
millisecondsTimeout
is a negative number other than -1, which represents an infinite time-out.
The underlying collection was modified outside this BlockingCollection<T> instance.
Remarks
The order in which an item is removed depends on the type of collection used to create the BlockingCollection<T> instance. When you create a BlockingCollection<T> object, you can specify the type of collection to use. For example, you could specify a ConcurrentQueue<T> object for first in, first out (FIFO) behavior, or a ConcurrentStack<T> object for last in, first out (LIFO) behavior. You can use any collection class that implements the IProducerConsumerCollection<T> interface. The default collection type for BlockingCollection<T> is ConcurrentQueue<T>.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1 |
UWP | 10.0 |
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
- Source:
- BlockingCollection.cs
Tries to remove an item from the BlockingCollection<T> in the specified time period.
public:
bool TryTake([Runtime::InteropServices::Out] T % item, int millisecondsTimeout);
public bool TryTake (out T item, int millisecondsTimeout);
member this.TryTake : 'T * int -> bool
Public Function TryTake (ByRef item As T, millisecondsTimeout As Integer) As Boolean
Parameters
- item
- T
The item to be removed from the collection.
- millisecondsTimeout
- Int32
The number of milliseconds to wait for the item to be removed, or Infinite (-1) to wait indefinitely.
Returns
true
if an item could be removed from the collection within the specified time; otherwise, false
.
Exceptions
The BlockingCollection<T> has been disposed.
millisecondsTimeout
is a negative number other than -1, which represents an infinite time-out.
The underlying collection was modified outside of this BlockingCollection<T> instance.
Remarks
The order in which an item is removed depends on the type of collection used to create the BlockingCollection<T> instance. When you create a BlockingCollection<T>, you can specify the type of collection to use. For example, you could specify a ConcurrentQueue<T> object for first in, first out (FIFO) behavior, or a ConcurrentStack<T> object for last in, first out (LIFO) behavior. You can use any collection class that implements the IProducerConsumerCollection<T> interface. The default collection type for BlockingCollection<T> is ConcurrentQueue<T>.
See also
Applies to
.NET 9 and other versions
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1 |
UWP | 10.0 |
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