SafeBuffer.AcquirePointer Method (Byte*)

.NET Framework (current version)
 

Obtains a pointer from a SafeBuffer object for a block of memory.

This API is not CLS-compliant.

Namespace:   System.Runtime.InteropServices
Assembly:  mscorlib (in mscorlib.dll)

[CLSCompliantAttribute(false)]
public unsafe void AcquirePointer(
	ref byte* pointer
)

Parameters

pointer
Type: System.Byte*

A byte pointer, passed by reference, to receive the pointer from within the SafeBuffer object. You must set this pointer to null before you call this method.

Exception Condition
InvalidOperationException

The SafeBuffer.Initialize method has not been called.

When AcquirePointer returns, you should perform bounds checking by verifying that the pointer parameter is null. If it is not null, you must call the SafeBuffer.ReleasePointer method in a constrained execution region (CER).

AcquirePointer calls the SafeHandle.DangerousAddRef method and exposes the pointer. Unlike the Read<T> method, it does not change the current position of the pointer.

The following exampledemonstrates how to use the AcquirePointer method:

byte* pointer = null;
RuntimeHelpers.PrepareConstrainedRegions();
try {
    MySafeBuffer.AcquirePointer(ref pointer);
    // Use pointer here, with your own bounds checking.
    }
finally {
    if (pointer != null)
        MySafeBuffer.ReleasePointer();
    }

If you cast pointer (which is a pointer to a byte) as a pointer to a different type (T*), you may have pointer alignment issues.

You must take responsibility for all bounds checking with this pointer.

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