Difference between NULL and null

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what is the equivalent of NULL of C++ in C#?

What I have tried:

Null has a default value 0. it can be used as bool,integer, pointer. But C# null is used when we are not pointing to some object. I am not sure whether null can be used in place of NULL in C#.

Posted 17-May-18 2:16am

hamid18

Updated 17-May-18 5:30am

v3

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User 7429338 · Accepted Answer · 2018-05-17T02:26:00

Solution 1

There's no equivalent that can be used in exactly the same way. What you assign depends on how you want to use it:

o is an int with value 0:

object o = 0;

o is a bool with value false:

object o = false;

o is an unassigned object:

object o = null;

Posted 17-May-18 2:26am

User 7429338

Updated 17-May-18 2:27am

v2

phil.o · Accepted Answer · 2018-05-17T02:28:00

NULL in C++ is just a macro which yields to a zero-pointer (a memory address of zero, meaning no address for that variable really).
The answer to your question is not straightforward: use null in C# to denote the absence of a reference to any object (for managed code); if you are trying to manipulate pointers from C# (which I actually do not recommend unless you really know what you are doing), you could use IntPtr.Zero instead.

CPallini · Accepted Answer · 2018-05-17T02:42:00

Solution 3

Quote:
Null has a default value 0

Roughly, see NULL - cppreference.com[^].

C++ and C# are rather different programming languages. So you risk to compare apple with oranges.

Posted 17-May-18 2:42am

CPallini

Richard MacCutchan · Accepted Answer · 2018-05-17T02:54:00

Solution 4

NULL is the old macro used in C-language. For C++ you should use nullptr. For C# use null.

Posted 17-May-18 2:54am

Richard MacCutchan

Comments

CPallini 17-May-18 9:01am

Go King Richard, go!
5.

Richard MacCutchan 17-May-18 9:49am

Only a prince now :(

Richard Deeming · Accepted Answer · 2018-05-17T05:31:00

Solution 5

If you just want to initialize a variable to its default value:
Default value expressions (C# Programming Guide) | Microsoft Docs[^]

Posted 17-May-18 5:31am

Richard Deeming