understanding subnetting

Deep understanding of CSS Media queries and deep understanding of css* Contents [1] media type [2] media attributes [3] syntax When it comes to responsive design, media queries are indispensable. It is generally considered that media queries are newly added to CSS3. In fact, CSS2 already exists, and CSS3 adds media attributes and use cases (not supported by IE8-browser ). This topic describes the content of

A deep understanding of the block concept in Ruby and a deep understanding of rubyblock Block in Ruby is generally translated into code blocks, which seem a bit strange at the beginning, because there is no such thing in many languages. In fact, it is not bad.First-class function and Higher-order function The First-class function and Higher-order function are concepts in functional programming languages. Th

Understanding of the assembly and understanding of the Assembly CLR interprets an assembly as a collection of one or more types of definition files and resource files. Generally, files suffixed with dll or exe are actually an assembly. Add resource files to an assembly. For example, if you commonly Add a Special icon to a Winform desktop program, you can select project "properties" in Visual Studio ", then

First understanding of PHP (1) Basic syntax, first understanding of php basic syntax. I first got to know the basic syntax of PHP (I). I first got to know the basic syntax of php and was always ready to learn PHP. as a result, there was always a problem some time ago, which was delayed for a while. Catch up now! This series only talks about basic PHP (1) and basic php syntax. I have been preparing to learn

KVO-understanding and simple use, KVO-understanding and simple useKVO is the key value observing (key value listening/Observer mode)/is a callback mechanism observer mode: A target object manages all the observer objects dependent on IT/and actively notifies the observer object when its own status changes/this brake notification is usually done by calling the interface methods provided by each observer obje

Javascript: a deep understanding of basic Javascript knowledge and a deep understanding of javascriptThe eval global function is shown in the loader of dojo as the next function. Var eval _ = new Function ('Return eval (arguments [0]); '); // The Function runs in the top-level scope, but the running efficiency is slower, however, this method does not pollute global variables and calls the top-level scope ev

Deep understanding of java Nested classes and internal classes, and deep understanding of java Nested classes 1. What are nested classes and internal classes? You can define another class within a class. This class is called the nested classes. It has two types: static nested class and non-static nested class. Static Nested classes are rarely used. The most important is non-static Nested classes, that is, t

Personal Understanding of epollhup and personal understanding of epollhup 1. Cause Due to the recent test of the asynchronous connect function, it is found that the epollhup event will continuously occur when a socket is added to the epoll listening queue in advance. 2. Example ........ IEpoll = epoll_create (1 ); IFd = socket (AF_INET, SOCK_STREAM, 0 ); StEvent. events = EPOLL_IN; StEvent. data. u3

Understanding and practice of GCD, and GCD understanding and practiceGCD GCD, full Grand Central Dispatch, is a solution developed by Apple for multi-core parallel processing. It is implemented in C language, but it is very convenient to use because block is used to process callback. In addition, GCD automatically manages the thread lifecycle, which does not need to be managed.Tasks and queues GCD has two i

Operating System: management process understanding, operating system management process understanding I recently started to read the operating system book (which is not in this direction). I still cannot fully understand it when I read the book, so let's simply summarize it. 1.A process (Monitors, also known as a monitor) is a program structure. Multiple working threads in the structure form multiple subpro

Deep understanding of the unit of length in CSS, deep understanding of css Length* Directory [1] px [2] in [3] cm [4] mm [5] q [6] pt [7] pc [8] em [9] rem [10] ex [11] ch [12] ext [13] vw [14] vmin [15] vmax This article introduces the main knowledge of the unit of length in CSS by dividing it into absolute length units and relative length units. Absolute length unit The absolute length unit represents a p

Recently, some good websites have been found in other countries.Article, Collected, sorted, and added to your understanding, recorded as notes, so that you can have memories in the future. ASP. net is a very powerful platform for building Web applications. It provides great flexibility and capabilities so that it can be used to build all types of Web applications. most people are only familiar with high-level frameworks such as webforms and WebServi

First understanding of PHP (4) PDO object configuration and use, first understanding of pdo I. PDO Concept PDO is actually a database abstraction layer. With PDO programming, you can easily change the database at any time in subsequent operations without changing the source code. Shows the location of PDO: Phptest, "root", "123 "); This completes the initialization of the PDO object. The connected database

In-depth understanding of concurrency (1), in-depth understanding of concurrency ( 1. Why concurrency?Perhaps the first reason we think of is to make the program run faster. Indeed, for a multi-processor machine, each task is allocated to multiple CPUs using concurrency, it enables faster program execution.However, when a concurrent program is run on a single processor machine, the cost of context switchin

A deep understanding of the JavaScript series (27): The Builder mode of design patterns, and a deep understanding of javascriptIntroduction In a software system, sometimes it is faced with the creation of "a complex object", which is usually composed of sub-objects of each part using a certain algorithm; due to changes in requirements, the various parts of this complex object often face drastic changes, but

In-depth understanding of the JavaScript series (13): This? Yes, this !, Understanding javascriptIntroduction In this article, we will discuss more details directly related to the execution context. The topic of the discussion is the this keyword. Practice has proved that this topic is very difficult, and this often occurs in different execution contexts. Many programmers tend to think that in programming l

A deep understanding of the JavaScript series (31): the proxy mode of the design mode, and a deep understanding of javascriptIntroduction Proxy, as its name implies, is to help others do things. The GoF defines the proxy mode as follows: Proxy mode, which provides a Proxy for other objects to control access to this object. The proxy mode allows the proxy object to control the reference of a specific object.

W3C understanding: understanding of the relationship between Party discipline and national lawThere are two standards available for website development: W3C or IE, because IE is not compatible with W3C in many places. That is to say, if your website is developed by W3C, there will be issues with IE display, if you develop it based on IE, on the one hand, IE6, 7, and 8 versions are not compatible with each o

Understanding of fork functions and understanding of fork Functions Header file: # include pid_t fork (void); 1. Create a sub-process and return-1 If the sub-process fails.2. Call once and return twice. The child process PID and 0 are returned respectively in the parent and child processes. Using different return values, you can write different processing branches for the parent and child processes respe

DWZ (1): First understanding of the framework and first understanding of the dwz framework The DWZ rich client framework (jQuery RIAframework) is an open-source Ajax RIA framework developed by Chinese people based on jQuery. The design goal of the DWZ rich client framework is simple and practical, easy to expand, fast development, RIA ideas, and lightweight. The DWZ framework supports HTML extension instead