Article 1: Understanding C # --------- C # notes,

Article 1: Understanding C # --------- C # notes,

I.What is. NET?

. NET: the. Net Framework is a platform and a technology.

II. Net FrameworkWhat is the main component of the framework?

Net Framework:

 

1> class library (FCL)

2> common language (CLR)

III.. NETHow is the program compiled?

1. Write source code

2. Compile the source code into Microsoft intermediate code (MSIL)

3. Hand the intermediate code to the CLR real-time Compiler (JIT)

4. JIT converts intermediate code into CPU commands corresponding to the platform

5. Give the CPU command to the CPU for execution.

4. managed code and non-managed code

1> code managed by CLR is called managed code (C # yes)

2> Codes not managed by CLR are called unmanaged codes.

3> what are the advantages and disadvantages of managed code?

Principle: CLR creates an independent memory space for each managed program, and prohibits other programs from accessing this memory.

Other programs;

Disadvantage: the running efficiency is relatively low.

Advantage: high security. Applicable to high security requirements.

 

C Language

…… Main () {println ("hello world ");}

Here, the main () function is the main module function in C language, and the white point is the entry of the program.

Println () is a character that is displayed on the screen.

…… "A file appears after saving", which is used to save your source code. That is to say, the next time you modify the source code, you can open this file to continue modification.

…… "Code together becomes an EXE file". Click the "compile" menu provided by the program to edit and connect the appeal code to form an executable EXE file. Double-click the EXE file to display the "hello world" text on the screen.

A preliminary understanding of a graphic

You can draw one line (four points in the same line)
Or four (only three vertices are collocated)
Or six (any three points are not collocated)