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What this article brings to you is about what is BFC? What is the use of BFC in CSS? , there is a certain reference value, the need for friends can refer to, I hope you have some help. What is BFC (Block formatting Context) Formatting context (format context) is a concept in the CSS2.1 specification. It is a rendered

What is LinuxThe same set of operating systems cannot be run on a platform of different architectures.Refer to the HARDWARE function function and modify your operating system program code, the revised operating system will be able to run on another hardware platform. This is the software migration .Linux is an open-source operating system, so its program code can be adapted to run on a variety of machines. Linux is portable .Linux provides a complete

This is an Android UI design slide from the official Android Developer blog, and 51CTO translators will be able to help the Android developer by translating 5 parts of the tutorial. This article is the first part of Google's Android UI design tips: What to do and what not to do. This article is the first part of Google's Android UI design tips: What to do and

programmers in addition to develop to look at the official document reading habits also need to have their own learning and communication platform, recommend a few source download site, you can go to the above learning, good source is suitable for beginners to learn faster. read someone else's code. Being a developer is a common thing to do. One is to learn a new programming language by reading someone else's code is the best way to learn, and also to accumulate programming experience. The first

If you want to enter the IT industry, if you are ready to master a new technology, then choose HTML5. Recently, we interviewed the well-known network hacker security expert Guoshenghua, to help you understand today's most important technology. In this article, Guoshenghua, a hacker security expert, answered 3 questions about HTML5.HTML is at the heart of modern websites and applications, so you must master it before you learn other programming languages, such as Javascript,java or CSS. With the

What Hadoop is. (1) Hadoop is an open source framework for writing and running distributed applications to handle large-scale data, designed for offline and large-scale data analysis, and is not suitable for online transaction processing patterns that randomly read and write to several records. Hadoop=hdfs (file system, data storage technology related) + Mapreduce (processing), Hadoop data source can be any form, in the processing of semi-structured a

There is no doubt that the Linux kernel needs to manage all the hardware devices connected to the computer. If you want to manage these devices, you need to communicate with them first, there are generally two scenarios for this functionality:1. Polling (polling) allows the kernel to periodically query the status of the device, and then make the corresponding processing;2. Interrupt (interrupt) allows the hardware to signal to the kernel when needed (the kernel is active for the hardware).The fi

What is flex and what is the relationship between Flex and Flash? (Turn) Flex is the presentation Server (presentation service) released by Macromedia, an application of the Java Web container or. NET Server, Generates a corresponding. swf file, based on the. mxml file (pure XML description file and ActionScript), delivered to the client, interpreted by the client's Flash Player or Shockwave Player, giving

To find out what wamp5 is? What's the use? We have to understand the WAMP site environment, before we have introduced what is the lamp host? , in fact, Wamp is the same, that is, Windows system plus apache,mysql and PHP built the Web environment, referred to as Wamp, after the amp, we will briefly describe what the WAMP5 and the main purpose. 　　 　　

What does HDR mean? High dynamic range images (high-dynamic range, or HDR), which can provide more dynamic range and image details than ordinary images, based on LDR (Low-dynamic range) images of different exposure times, The final HDR image [1] is synthesized using LDR images with each exposure time relative to the best detail, which can better reflect the visual effects in the real environment. Concept As described above HDR, for the short name o

1.c# in what case (int) Under what circumstances use Convert.ToInt32? For example, if you have a string of 3, whether you want to convert it to int (int) 3, or Convert.ToInt32 (3); Or two can be used, why? Answer: Both are converted to integral types, but they are of different lengths. int is 16 bits, and the bottom one is 32-bit. First of all, I would like to point out that in C #, int is actually System.I

what circumstances are indexes, but not used?Indexes do not always take effect, such as the following, which will invalidate the index : If there is or in the condition, even if some of the conditions in the index are not used ( which is why the use of or is minimized ), in the example user_id no index Note: If you want to use or, and you want the index to take effect, you can only index each column in the OR conditio

prevent inconsistent data. Database at design time, the primary key plays a very important role.The primary key guarantees that the record is unique and the primary key domain is not empty, and the database management system automatically generates a unique index for the primary key, so the primary key is also a special index.2. There can be multiple unique indexes in a table, but only one primary key.3. The primary key column does not allow null values, and the uniqueness index column allows n

What is a data warehouse, and what is the difference between a databaseDataWarehouseis a subject-oriented (Subject oriented), integrated (integrate), A relatively stable (non-volatile), data collection that reflects historical changes (timeVariant) to support management decisions. (1) topic-oriented: Index data in the warehouse is organized according to a certain subject domain. (2) Integration: Refers to t

Modularization is a method of separating the system into independent functional parts, which can divide the system into independent functional parts, define the module interface strictly, and have the transparency between the modules.Now backbone, Emberjs, Spinejs, BATMANJS and other MVC framework attack. CommonJS, AMD, NodeJS, Requirejs, Seajs, Curljs and other modular JavaScript are on the go. Web front-end has evolved into a large front end, the development of the Web front-end faster.1) Let'

Effectively optimize the performance of the VPS, improve the running speed of the VPS server, in addition to a reasonable configuration of the Web server, more is the need for us to be able to optimize the Web site procedures and website database, the optimization of the site database is the most basic optimization measures is to establish the database index, here on What is a database index? What are the

What are the built-in objects for JSPs? What are the roles? (Minimum of three)Answer:1) The request represents the HttpServletRequest object. It contains information about browser requests and provides several useful methods for obtaining cookies, headers, and session data. 2) response represents the HttpServletResponse object and provides several methods for setting the response to the browser (such as coo

1, the serialization is what. This is simply to save the state of the various objects in memory, and to read the saved object state again. Although you can save object States in a variety of ways, Java provides you with a mechanism to preserve the state of objects better than yourself, and that is serialization. 2, under what circumstances need to serialize a when you want to save the object in memory in

Reply formatApplication field ... You like the JS library name ... function (a sentence)Web .... jquery ..... Well-known DOM operations librarySeajs. JS's management frameworkEjs ... JS template engine without learning costAsync ... Asynchronous management Library, the most used in the Nodejs, can also use in the front-endUnderscore. js extension, add a lot of methodsNodejs ... Express ... nodejs the most popular HTTP service Framework .Mongo-sql ... Convert JSON to MySQL. Cheer it up! No need t

What do you call office software? The word office automation is very familiar to everyone, its English name is office automation, abbreviation OA. In the early 80, when the domestic computer technology increasingly popular, office automation is almost synonymous with computer applications, many units or individuals to buy computers is to print documents, until today, this view is still very popular, which from a side reflects the office automation in