define defragment

This article to share the content is detailed in the PHP constant: Define and const difference, has a certain reference value, the need for friends can refer to A constant is a simple identifier. This value cannot be changed during script execution (in addition to the so-called magic constants, they are not constants). Constants are case sensitive by default. Usually, constant identifiers are always uppercase. can be used

"Q" When defining constants in PHP, what is the difference between const and define? The "answer" uses the const to make the code easy to read, and the const itself is a language structure, and define is a function. In addition, const is much faster to compile than define. (1). Const is used to define a class member v

1. const is used for defining class member variables. once defined, the value cannot be changed. Define defines global constants that can be accessed anywhere. 2. define cannot be defined in the class, but const can. 3. const cannot define the constant if (...) {constFOO amp; #39;... SyntaxHigh in the condition statement. 1. const is used for defining class memb

# Ifndef # define # endif usage, # Ifndef # define # endif usage # Ifndef # Ifndef in the header, which is critical. For example, you have two C files, both of which include the same header file. During compilation, these two C files need to be compiled into a runable file together, so the problem arises and a large number of declarations conflict. Put the header file content in # ifndef and # endif. Wheth

1. Wide screen height and common size#define SCREEN_WIDTH ([UIScreen mainscreen].bounds.size.width)#define Screen_height ([UIScreen mainscreen].bounds.size.height)#define Navigationbar_height 44.0f#define Tabbar_height 49.0f#define Statusbar_height 20.0f#

Parse the differences between static, const, and define in php. Define: macros can be used not only to replace constant values, but also to replace expressions or even code segments. (Macros have powerful functions but are prone to errors, so their advantages and disadvantages are quite large. Define section:Macros can be used not only to replace constant values,

1. Simple define Definition # Deprecision MAX 1000 A simple max is defined. It represents 1000. If you writeFor (I = 0; I {................}The compiler replaces MAX with 1000 before processing this code. 2. define's "Function Definition" Define can accept some parameters as the function does, as follows: # Define max (x, y) (x)> (y )? (X) :( y ); This definition

This article mainly introduces how to use hidef extension in PHP to replace define to improve the performance. This article focuses on testing the performance of hidef and introduces the installation method and use example. For more information, see This article mainly introduces how to use hidef extension in PHP to replace define to improve the performance. This article focuses on testing the performance o

What is a const? What is a # define? What's the use of them? What difference do they have? What should I do with it? Summarize 1. What is a const?Const is a keyword (modifier) in C/s + +, which is typically used to define a constant that, since it is called a constant, cannot modify its value later.Const definition Constants2. What is a #

struct, so it is invented: typedef struct TAGPOINT {int x; int y;} Point;Point P1; This is less than the original way to write a struct, more convenient, especially in the large use of timePerhaps, in C + +, this use of TypeDef is not very large, but understanding of it, to master the old code is still helpful, after all, we may encounter in the project earlier legacy code.Use three:Use typedef to define platform-independent types. For example, to

Define dimension granularity in a measurement value group : Users may need to define fact data table dimensions of different granularities or specificity for different purposes. For example, sales data for distributors or Internet sales can be recorded once a day, while sales quota information may be recorded on a monthly or quarterly basis. In these cases, you may need time dimensions to have different gr

Use the typedef statement to define the array type 1. Definition Format of one-dimensional array type Typedef For example: (1) typedef int vector [10]; (2) typedef char strings [80]; (3) typedef short int array [N]; The first statement defines an array-type vector with an element type of int and 10 elements. If typedef is not used, the array definition is changed, it only defines an array vector whose element type is int and contains 10 elements.

# Ifndef # Ifndef in the header, which is critical. For example, you have two C files, both of which include the same header file. During compilation, these two C files need to be compiled into a runable file together, so the problem arises and a large number of declarations conflict. Put the header file content in # ifndef and # endif. Whether or not your header file will be referenced by multiple files, you must add this. The general format is as follows: # Ifndef #

1. const is used for defining class member variables. Once defined, the value cannot be changed. Define defines global constants that can be accessed anywhere. 2. Define cannot be defined in the class, But const can.3. Const cannot define constants in condition statements. If (...){Const Foo = 'bar'; // invalid}ButIf (...){

In the previous article, there is a pre-compiled directive that says # include, and a common precompiled directive: #define. Its surface meaning is defined, which is usually said to "define constants", but its real function is to replace;Such as:#define SUCCESS 1The whole sentence is to define a macro substitution wher

1. Const is used for class member variable definition once defined and cannot change its value. Define defines global constants that can be accessed anywhere. 2, define can not be defined in the class and Const. 3. Const cannot define constants in conditional statements Copy Code code as follows: if (...) { Const FOO = ' BAR '; Invalid } But

Css|frontpage Description: The current version of FrontPage is Frontpagexp (FrontPage 2002), this article is Frontpage2000, but the method described in this article is basically applicable in Frontpagexp! In addition, this is only discussed in Frontpage2000 how to define CSS, as for the knowledge of CSS please refer to the relevant information. When many people find it convenient to define CSS in DW4, they

Today continue to try the version of Seajs 2.3, then do something about the demo good, just a simple data template bar, and then through some other details in-depth study First look at the directory structure, according to the official demo erection Index.html is just a simple entry file and SEAJS configuration item, at the bottom there is a seajs.use load Crontroller module and then callback the exposed combine method Crontroller module, there are some official instructions and debugging, tri

[Convert] # ifndef # define # endif usage (Arrangement) Original Author: icwk # Ifndef # Ifndef in the header, which is critical. For example, you have two C files, both of which include the same header file. During compilation, these two C files need to be compiled into a runable file together, so the problem arises and a large number of declarations conflict. Put the header file content in # ifndef and # endif. Whether or not your header file will b

Recently in the cloud Platform for the initial code architecture, encountered a constant definition speed comparison problem, so do a comparison. The APC extension for PHP is described in the following paragraph in the PHP Manual: http://cn.php.net/manual/zh/function.apc-define-constants.php Define () is notoriously slow. Since the main benefit of APC is to increase the performance of scripts/applications,