[RESOLVED] pointer newbie question

[vbbit]

Hello, I am new to C#, and I came across a tutorial about pointer:

int *x ;

Declares a pointer variable x, which can hold the address of an int type. The reference operator (&) can be used to get the memory address of a variable.

int x = 100;

The &x gives the memory address of the variable x, which we can assign to a pointer variable

I don't understand what that "address of" mean?

[jmcilhinney]

The address of an object is the location in memory at which it resides. Each byte in memory has a numerical address the address of an object is the address of the first byte in memory it occupies. A pointer is a variable that contains the memory address of an object. If you have a non-pointer variable you can use the "&" operator to its address, which can then be assigned to a pointer variable.

If you're new to C# then I don't think you need be worrying about unsafe code and pointers just yet, unless you are already a relatively advanced programmer. The .NET Framework is constructed in such a way that you don't need pointers in the vast majority of situations. There are some situations where using pointers can dramatically speed up computationally-intensive sections of code, but for the most part they are unnecessary.

[r0k3t]

just to expand on that - think of a method that you create. You pass it a value... let's say x, normally you are passing by value, meaning that you pass a copy of the variable x into your method, when you do whatever computation if you don't return that value when the execution is complete then the value of x isn't changed. however if you where to pass by reference it is like saying "there is a variable stored at this memory location" if you then "follow the pointer" and do some computation then the value of x is changed in that case.

as was said before - C# doesn't really need pointers for most of what the world is doing with it. I avoid them, that is probably good advice.

[wossname]

Pointers can make it much easier to use the API and also interface with binaries created in other programming languages (C/C++, ASM, Delphi...).