List(T).ForEach Method

Performs the specified action on each element of the List(T).

Namespace:  System.Collections.Generic
Assemblies:   mscorlib (in mscorlib.dll)
  System.Collections (in System.Collections.dll)

member ForEach : 
        action:Action<'T> -> unit


Type: System.Action(T)

The Action(T) delegate to perform on each element of the List(T).


action is a null reference (Nothing in Visual Basic).

The Action(T) is a delegate to a method that performs an action on the object passed to it. The elements of the current List(T) are individually passed to the Action(T) delegate.

This method is an O(n) operation, where n is Count.

Modifying the underlying collection in the body of the Action(T) delegate is not supported and causes undefined behavior.

The following example demonstrates the use of the Action(T) delegate to print the contents of a List(T) object. In this example the Print method is used to display the contents of the list to the console.


In addition to displaying the contents using the Print method, the C# example demonstrates the use of anonymous methods to display the results to the console.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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