How can I get the memory address of a feilds in C#?

Question

0.00/5 (No votes)

See more:

I created an object from a class in C#. Is it possible to retrieve its memory location and address using C# code?

What I have tried:

i have tried this code but i got error at this line

IntPtr address = GCHandle.AddrOfPinnedObject(handle);

of the code

the full code is

C#

Person person_1 =  new Person("mina remon shaker");

// Get the FieldInfo for "myField"
FieldInfo? fieldInfo = typeof(Person).GetField("Name");

// Pin the object in memory (required for getting address)
GCHandle handle = GCHandle.Alloc(person_1, GCHandleType.Pinned);

// Get the address of the pinned object
IntPtr address = GCHandle.AddrOfPinnedObject(handle);

// Free the handle
handle.Free();

// "address" now points to the memory location of the entire object
// You can't directly access the address of the field within the object

Console.WriteLine("Object address: 0x{0:X}", address.ToInt64());

Posted 21-May-24 7:55am

Member 14479161

Add a Solution

Comments

Pete O'Hanlon 21-May-24 16:37pm

What error did you get?

Member 14479161 22-May-24 22:12pm

Error CS1501 No overload for method 'AddrOfPinnedObject' takes 1 arguments C#ForBeginners D:\Projects\C#ForBeginners\C#ForBeginners\Program.cs 53 Active

Dave Kreskowiak 22-May-24 23:38pm

That's because AddrOfPinnedObject doesn't take any arguments. When you called GCHandle.Alloc, it returns a GCHandle object, which you stored in "handle". The correct code should have been:

GCHandle handle = GCHandle.Alloc(person_1, GCHandleType.Pinned);
IntPtr address = handle.AddrOfPinnedObject();

But keep in mind, the instant you call handle.Free();, that address isn't valid anymore.

Member 14479161 25-May-24 22:32pm

this means it is like cleard removed correct

Dave Kreskowiak 25-May-24 23:46pm

No. Like I said before, once an object is no longer pinned, the garbage collector is free to move the object in memory any time it wants.

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Dave Kreskowiak · Answer 1 · 2024-05-21T10:41:00

Not sure why you would want to do this because the GC can move heap allocated objects around at any time, but you can do this:

C#

unsafe
{
    BaseClass baseClass = new();
    BaseClass* ptr = &baseClass;

    Console.WriteLine($"{(long)ptr:X}");
}

You need to enable unsafe code in your project properties and you're going to get a bunch of warnings about this, but the code will still compile and run.