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SafeBuffer.AcquirePointer(Byte*) Method

Definition

Important

This API is not CLS-compliant.

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

public:
 void AcquirePointer(System::Byte* % pointer);
[System.CLSCompliant(false)]
public void AcquirePointer (ref byte* pointer);
[<System.CLSCompliant(false)>]
member this.AcquirePointer : Byte* -> unit

Parameters

pointer
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.

Attributes

Exceptions

The Initialize method has not been called.

Remarks

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.

The following example demonstrates 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.

Applies to