Contract.ForAll<'T> Method (IEnumerable<'T>, Predicate<'T>)


Determines whether all the elements in a collection exist within a function.

Namespace:   System.Diagnostics.Contracts
Assembly:  mscorlib (in mscorlib.dll)

static member ForAll<'T> : 
        collection:IEnumerable<'T> *
        predicate:Predicate<'T> -> bool


Type: System.Collections.Generic.IEnumerable<'T>

The collection from which elements of type T will be drawn to pass to predicate.

Type: System.Predicate<'T>

The function to evaluate for the existence of all the elements in collection.

Return Value

Type: System.Boolean

true if and only if predicate returns true for all elements of type T in collection.

Type Parameters


The type that is contained in collection.

Exception Condition

collection or predicate is null.

The following example demonstrates how to use the ForAll<'T> method to determine whether a collection has a null element.

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

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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