C # Advanced Programming 75 days----C # using pointers

syntax for using pointers in C #

Suppose you want to use pointers in C # , First configure the project :

Do you see the attributes? Click :

Do you see that consent-insecure code? selected

The operation of the pointer and address is then placed in the unsafe statement block . Use unsafe keyword is telling the compiler that the code here is unsafe .

use of unsafe keyword :

(1) Before the function , Modify the function , indicating that the function of the inside or the shape of the function involves a pointer operation :

unsafe static void FastCopy (byte[] src, byte[] DST, int count)

{

Unsafe Context:can use pointers here.

}

The orientation of the unsafe context extends from the list of references to the end of the method , So the pointer is used as the function's parameter to use the unsafekeyword.

(2) Placing pointers on unsafe blocks declared by unsafe

unsafe{

Unsafe Context:can Use pointers here

}

Case :

Using System;

Using System.Collections.Generic;

Using System.Linq;

Using System.Text;

Using System.Threading.Tasks;

using pointers in namespace Csharp

{

Class Program

{

static void Main (string[] args)

{

int i = 1;

Unsafe

{

Increment (&i);

}

Console.WriteLine (i+ "\ n");

demonstrates how to manipulate strings with pointers

string s = "Code Project is cool";

Console.WriteLine ("The original string:");

Console.WriteLine ("{0}\n", s);

Char[] B = new char[100];

copies the characters of the specified bibliography to a specified position in a Unicode character array from the specified position in this instance

S.copyto (0, B, 0, 20);

Console.WriteLine ("The Encode string:");

Unsafe

{

Fixed (char* p = b)

{

Nencodedecode (P);

}

}

for (int t = 0; t < t++)

{

Console.WriteLine (B[t]);

}

Console.WriteLine ("\ n");

Console.WriteLine ("The Decoded string:");

Unsafe

{

Fixed (char* p = b)

{

Nencodedecode (P);

}

}

for (int t = 0; t < t++)

Console.Write (B[t]);

Console.WriteLine ();

Console.readkey ();

}

Unsafe public static void Increment (int* p)

{

*p = *p + 1;

}

<summary>

An operation that encodes a string through an XOR operation . Suppose you put a string into this

function , The string is encoded , Assuming that the encoded character is fed into the function ,

This string will

decoding

</summary>

<param name= "S" ></param>

Unsafe public static void Nencodedecode (char* s)

{

int W;

for (int i = 0; i <; i++)

{

w = (int) * (s + i);

w = w ^ 5;// bitwise XOR

* (s + i) = (char) W;

}

}

}

}

When the fixed is used, the following is necessary to introduce it :

Fixed statements can only be in the context of today's insecure ,c# compiler just agree fixed Span style= "font-family: Arial" > The pointer to a managed variable is assigned cannot be changed in fixed The pointer initialized in the statement

The fixed statement prevents the garbage collector from locating the movable variable . when you use it before a statement or function fixed when , you are telling . NET Platform's garbage collector , before this statement or function is finished running , Do not reclaim the memory space that it occupies .

C # Advanced Programming 75 days----C # using pointers