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UnmanagedMemoryStream.Initialize Method (Byte*, Int64, Int64, FileAccess)


Initializes a new instance of the UnmanagedMemoryStream class by using a pointer to an unmanaged memory location.

This API is not CLS-compliant.

Namespace:   System.IO
Assembly:  mscorlib (in mscorlib.dll)

protected unsafe void Initialize(
	byte* pointer,
	long length,
	long capacity,
	FileAccess access


Type: System.Byte*

A pointer to an unmanaged memory location.

Type: System.Int64

The length of the memory to use.

Type: System.Int64

The total amount of memory assigned to the stream.

Type: System.IO.FileAccess

One of the FileAccess values.

Exception Condition

The user does not have the required permission.


The pointer value is null.


The length value is less than zero.

- or -

The capacity value is less than zero.

- or -

The length value is large enough to cause an overflow.

This method is equivalent to the UnmanagedMemoryStream constructor. It supports methods that need to initialize the pointer before setting stream variables and, therefore, cannot call the parameterized constructor. Such methods should use the default constructor, UnmanagedMemoryStream(), initialize the pointer, and then invoke the Initialize method.


for accessing unmanaged memory.


requires full trust for the immediate caller. This member cannot be used by partially trusted or transparent code.

Universal Windows Platform
Available since 10
.NET Framework
Available since 2.0
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