CopyTo Method (T[])

List<'T>.CopyTo Method ('T[])


Copies the entire List<'T> to a compatible one-dimensional array, starting at the beginning of the target array.

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

member CopyTo : 
        array:'T[] -> unit


Type: 'T[]

The one-dimensional Array that is the destination of the elements copied from List<'T>. The Array must have zero-based indexing.

Exception Condition

array is null.


The number of elements in the source List<'T> is greater than the number of elements that the destination array can contain.

This method uses Array.Copy to copy the elements.

The elements are copied to the Array in the same order in which the enumerator iterates through the List<'T>.

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

The following example demonstrates all three overloads of the CopyTo method. A List<'T> of strings is created and populated with 5 strings. An empty string array of 15 elements is created, and the CopyTo('T[]) method overload is used to copy all the elements of the list to the array beginning at the first element of the array. The CopyTo('T[], Int32) method overload is used to copy all the elements of the list to the array beginning at array index 6 (leaving index 5 empty). Finally, the CopyTo(Int32, 'T[], Int32, Int32) method overload is used to copy 3 elements from the list, beginning with index 2, to the array beginning at array index 12 (leaving index 11 empty). The contents of the array are then displayed.

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

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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