Repost [patchwork, want to know]

What should net cool people know?

Anyone using. net

• What is the difference between a thread and a process?
• What is Windows service, its lifecycle and standard exeProgramWhat is the difference?
• What is the maximum memory size that a single process can access on windows? Is it the same as the maximum virtual memory of the system? What is the impact on system design?
• What is the difference between EXE and DLL?
• What is a strong type and what is a weak type? Which one is better? Why?
• What is PID? How to use the system in troubleshooting?
• How many processes can a single TCP/IP Port listen?
• What is GAC? What problems does it solve?

Intermediate. NET developers

• Describe the differences between interface-oriented, object-oriented, and Aspect-Oriented Programming
• What is interface? What is the difference between it and class?
• What is reflection?
• What is the difference between the XML Web Service using asmx and the. NET remoting using soap?
• Is the type system represented by XMLSCHEMA? Is CLS represented by XMLSCHEMA?
• What is the difference between early-binding and late-binding?
• Does calling assembly. Load calculate static reference or dynamic reference?
• When to use assembly. loadfrom? When to use assembly. LoadFile?
• What is Assembly qualified name? Is it a file name? What's the difference?
• Assembly. Load ("foo. dll"); is this statement correct?
• What is the difference between an assembly with strong signatures and an assembly without strong signatures?
• Can datetime be null?
• What is JIT? What is ngen? What are their limitations and benefits?
• In. Net CLR, how does a generation of Garbage Collector manage the object lifecycle? What is the end of uncertainty?
• What is the difference between finalize () and dispose?
• Is the using () syntax useful? What is idisposable? How it achieves the final certainty.
• What is tasklist/M "mscor?
• Differences between in-Proc and out-of-Proc
• Which technology in. Net can implement out-of-Proc communication?
• When you run a component in ASP. NET, which process does it run on Windows XP, Windows 2000, and Windows 2003 respectively?

Senior developers/architects

• Datetime. parse (mystring); this lineCodeWhat's the problem?
• What is PDB? Where should it be placed during debugging?
• What is cyclomatic complexity )? Why is it important?
• Write a standard lock () to create a critical section before and after the access variable. There must be a "double check ",
• What is fulltrust? Is the Assembly placed in GAC fulltrust?
• What are the benefits of adding the features that require security permissions to the code?
• What is the role of the gacutil/L | find/I "corillian" command?
• Why is the command Sn-T Foo. dll?
• What ports does DCOM need to open through the firewall? What is port 135 used?
• What are their purposes for comparing OOP and SOA?
• How does xmlserializer work? What ACL permissions does a process using this class need?
• Why not advocate catch (exception )?
• What is the difference between Debug. Write and trace. Write? Which one should I use?
• Is there a significant speed change between debug build and release build? Describe the reason.
• Does JIT occur in the unit of assembly or in the unit of method? What is the impact on the workspace?
• Comparison of abstract base classes and interfaces
• A. Is equals (B) the same as a = B?
• In object comparison, what are the meanings of the same object and the same object?
• How to implement deep copy in. Net )?
• Please explain iclonable
• What is packing?
• Is string a value type or a reference type?
• What are the advantages of the attribute-oriented mode used by xmlserializer? What problems have been solved?
• Why shouldn't the out parameter be used in. Net? Is it good?
• Can features be placed on parameters of a method? If yes, what is the purpose?

C # component developers

• When to use override? When to use new? What is shadowing?
• Differences between virtual, sealed, override, and abstract
• Foo. Bar, version = 2.0.205.0, culture = neutral, publickeytoken = 593777ae2d274679d explain the importance and function of each part of the string
• Differences between public, protected, private, and internal
• What are the benefits of using primary InterOP assembly (PIA?
• What mechanisms does nunit use to determine which methods to test?
• Catch (exception e) {Throw E;} and catch (exception e) {Throw ;}
• What is the difference between typeof (FOO) and myfoo. GetType?
• Public class c {public C (string a): this () {;}; public C () {;}} explains what happened in the first constructor? What is the use of this constructor?
• Why is this used? Can be used in the static method?

ASP. NET (UI) Developer

• Describes how a browser-based form post becomes a server-side event, such as buttonemedionclick.
• What is PostBack?
• What is viewstate? Is it encoded? Encrypted? Who will use viewstate?
• <Machinekey> Why is the element used? Which two ASP. NET technologies does it use?
• What are the three session state providers in ASP. NET 1.1 and their advantages and disadvantages?
• What is Web gardening? How to use it in design?
• Suppose there is an ASP. NET application, how many application objects are allowed in a single process? What about the two processes? What if two web gardening processes are enabled? What is the impact on the design?
• Will ASP. NET reuse threads between multiple requests? Does each httprequest have its own thread? Should you use ASP. NET Thread Local Storage?
• [Threadstatic] is the attribute useful in ASP. NET? Does it have any side effects? Is it good or bad?
• How to Use httphandler to simplify the existing design of providing verification images for. aspx pages
• What type of events does httpmodule subscribe? What is the impact on implementation? What should I do if I do not intend to re-compile the ASP. Ne application?
• Specifies the way to express any terminal (URL) and the way to route requests to that end point in ASP. NET.
• Explains how cookies work. An example of cookie abuse is provided.
• How important is httprequest. validateinput?
• What data is transmitted through HTTP header?
• Compare http get and post? What is head?
• Give at least 6 HTTP status codes and their meanings
• What is the working principle of IF-not-modified-since? How to Implement ASP. NET?
• <@ Outputcache %> and how to use varybyparam and varybyheader.
• How does varybycustom work?
• How to Use Q =? (Except q = 5) to implement ASP. net html output buffer and buffer expiration (such as http: // localhost/page. aspx? Q = 5 )?

XML developers

• What is the role of the XML namespace?
• When Will Dom be used? When is it not suitable? Is there a scaling limit?
• What is basic WS-I configuration? Where is it important?
• Write a small XML document, which uses the default namespace and a valid (prefix) namespace. The namespace must have the elements of the two namespaces respectively.
• What are the basic differences between elements and features?
• What is the difference between well-formed XML and valid XML?
• How to verify XML in. Net?
• Myxmldocument. selectnodes ("// mynode"); why is this code not good? When is it okay?
• Differences between xmlreader and event reader (SAX)
• What is the difference between xpathdocument and xmldocument? Under what circumstances should I use?
• What is the difference between "XML fragments" and "XML documents "?
• What is a standard XML format?
• What is the difference between the XML infoset specification and the xml dom? What is the problem solved by infoset?
• Compare DTD and XSD. What are their similarities and differences? Which one is better? Why?
• Does system. XML support DTD? If yes, how do I use it?
• Can XML Schema be represented as an object graph? Can an object chart be expressed as an XML schema?

7. Do not read books blindly.
When you look at the number of students, open the Directory and look at it. In the directory, you can find what you can accept. When you understand this, go to the system to see it, don't look at the source code of the built-in CD. You only need to follow the steps of the master to see the effect. If you read the source code, you will lose a chance to think about it, it may even lose n experience solving the problem.
8. Shaolin
It is said that yijinjing can cultivate all martial arts, but how is yijinjing practiced? It is the most important foundation to cultivate higher martial arts,
<Data Structure> <developer control not far away> <you must know. net> <JavaScript> is your first choice, because they tell you how to efficiently create tools instead of tools.

Single Responsibility Principle (SRP ).

The approximate meaning is displayed from the name. That is to say, each class has only one responsibility. Here, we need to understand it as the cause of the change. The combination of these two statements is the gof statement: each class should have only one reason for his change.

The OCP principle ).

I think everyone can understand the principle of openness and closure literally, that is, opening up the extension and closing the modification. A good software can be expanded without limit, and it does not need to modify the internal structure of the class (of course, this refers to the ideal situation, in fact, no matter how well-designed software, once extended, you must always modify the class ).

LSP,

I can't remember his specific translation. His content is that child classes must be able to replace parent classes. It seems to be the subclass replacement principle. I don't want to explain this too much. I want to understand all people who have learned Object-Oriented Knowledge. In inheritance, the parent class extracts the commonalities of the Child classes and extracts them. In this way, the Child class can replace the parent class.

Dip (dependency reversal principle ).

The content of DIP should depend on interfaces rather than programming. This is the most typical phenomenon in the design pattern. Almost every design pattern typically meets this principle. Here, let's take a look at the most typical facade (appearance mode ). The intent of the appearance mode is to provide a unified interface for a subsystem or sub-module, and then let the high-level module call this interface without knowing the implementation details in the subsystem.

 

 (1) FCL (. netframeworkclasslibrary):. NET Framework class library
FCL contains thousands of types, which are organized by namespace according to their functions.
Various. NET languages only define some rules, and we need to call the type in FCL to a large extent in actual use. These types allow us to use less language knowledge to create rich programs.
CLR and FCL support the following applications:
(1) XML Web Services
(2) web forms
(3) Windows Forms
(4) Windows Cui (console application)
(5) Windows Services (Windows SCM-Service Control Manager-managed service programs)
(6) Component Library
(2) CTS (Common Type System) General Type System
Type is the basis of CLR. Microsoft defines a formal specification -- CTS to describe the definition and behavior of the type.
CTS defines access control items for types and type members.
CTS defines the type of behavior to separate the language and code behavior: We can use C ++ to define our own types and members, or C # and VB to define them. However, the type of behavior is absolutely identical and has nothing to do with the language.
(3) CLS (Common Language Specification) Public Language Specification

 PE means portable executable (portable execution body ). It is the execution file format of the Win32 environment. Some of its features inherit from the Unix coff (Common Object File Format) file format. "Portable executable" means that the file format is cross-Win32 platform, even if windows runs on a non-Intel CPU, the PE Loader on any Win32 platform can recognize and use this file format.

In the file system, PE files are binary data, just like other files stored on disks. For the operating system, PE files can be considered as a carrier of specific information, if you want a computer system to execute a program, the program file carrier must conform to a specific format. To analyze the format of specific information carriers, analysts are required to have data analysis and encoding analysis capabilities. In the win32system, pefiles can be regarded as files of the .exe,. dll,. sys, And. scr types. These files are stored on disks in a regular format.

1. PE format Basics

The dos MZ header is a legacy product of the DOS era. It is a genetic gene of PE files. If a Win32 program can be executed under DOS, it only prompts: "This program cannot be run in DOS mode. then the execution is completed, prompting the executor that the program should be executed in the Win32 system.

The Dos Stub part is the DOS plug-in code, which is the 16-bit program code under DOS, just to display the above prompt data. This code is automatically added by the compiler during program compilation.

The PE Header is the real Win32 program format header, which includes various information in the PE format and guides the system to load and execute the program code.
Section table is the structure data of PE code and data, indicating where the system code segment is loaded and where the data segment is. For different PE files, the designer may require the file to include different data sections. Therefore, a section table is used as an index. The number of sections varies according to the actual situation. But there must be at least one section. If a program does not even have code, it cannot be called executable code. After section table, the number of sections is not fixed.

2. Program loading

When we double-click a file in explorer.exe (resource manager) and execute an executable program, the system starts a program loader based on the file extension, which is called loader. Loader will first check the dos mz header. If yes, it will continue to look for the PE Header. If neither of the two items exists, it will be considered as DoS 16-bit code. If only dos MZ header exists, while it indicates the position of the PE Header, the loader determines that the file is not a valid PE file and refuses to execute.

If both the DOS header and PE Header are valid, the loader maps the corresponding code and data to the memory according to the PE Header and Section Table instructions, then initialize the data according to different sections, and finally start to execute the program segment code.

 

 

 

Il, also referred to as the pencil or msil, is translated into Chinese as an intermediate language and is fully defined and standardized by the ECMA Organization (Standard ECMA-335. As the name implies, as the name implies, any CLR-compatible compiler generates intermediate language code, which is one of the infrastructure for implementing CLR cross-language. Il is like a bridge. Its Instruction Set exists independently of CPU instructions. It can be translated into local code execution by the JIT compiler at runtime, connecting any advanced language that complies with CLS specifications, is. NET platform provides the most basic support. In [what you must know. net] in the book, I used a whole chapter (chapter 3rd "Everything starts with IL") to introduce the basic content of Il, therefore, the basic content of Il, such as basic types, il analysis methods, Common commands, and basic operations, will not be described in this article. I will only summarize the basic content of Il:

• Il is an object-oriented machine language. Therefore, it has all the features of object-oriented language. Class, object, inheritance, polymorphism, and so on are still the basic concepts of IL language.
• The IL command is independent of the CPU command, and the CLR converts it to local code through the JIT compilation mechanism.
• Il and metadata are important to understand the operating mechanism of CLR, which is of great significance for us to open the secret of CLR.