function exists

The design of Collection classes in PHP is analyzed. It has been developed with. net for many years. Recently, I came into contact with php and found that php is also very fun. However, it is found that there is no Collection class in it, only an

PHP is rarely used but has powerful functions. Call_user_func_array calls a function call_user_func in the form of an array to call an existing function create_function to create a function func_get_arg to obtain the parameter call_user_func_array

In php development, we often choose to provide pre-defined variables, constants, or functions to determine if they exist. Next we will introduce some frequently used judgment constants, variables, and functions to determine whether they exist in

Copy codeThe Code is as follows:If (defined ('const _ name ')){// Do something} Isset is used for variable detection. Note that if the variable is not declared or declared, the value is NULL, and isset returns FALSE, for example: Copy codeThe Code

This article provides a detailed analysis of Collection classes in PHP. For more information, see This article provides a detailed analysis of Collection classes in PHP. For more information, see It has been developed with. net for many years.

Text: Understanding the keyword extern in the C language Recently wrote a C program, compile the variable duplicate definition of the error, you see no errors found. Using Google found that the extern understanding is not thorough, I

In most languages, there is a reflection mechanism. In effect, reflection is to increase the dynamic description ability of the program. Popular is the decision that allows users to participate in code execution. At the time of program writing, we

1. Call_user_func and Call_user_func_arrayThe above two functions call the function in a different parameter form. See the example below:Class Demo{public static function Action1 (){echo "This is demo::action1.";}Public Function Action2 (){echo

Php deep learning Note 2 (built-in function) 1. call _? User _? Func _? Array calls a user-defined function. The first parameter is the function name, The second parameter is that the function parameter must be an index array. Function foobar ($

Use the strpos () function to do this. if the return value of this function exists, otherwise false is returned. in this way, if the return value of this function is false, it indicates that there is no limit. Use oop and mysql extension to complete

Recently, I wanted to learn Redis by using Redis's source code. Although the usual work is not used much, but the Redis is still more interested in, after all, its performance is good. Redis is an open source project that we can use to understand

Copy CodeThe code is as follows: Class Event extends stdclass{ public $target =null; Public $type =null; /** * Create Event * @param string $type */ Public function __construct ($type) { $this->type=trim ($type); } /** * Get Event String */ Public

With. NET development for many years, recently contacted PHP, found PHP is also very fun. However, it is found that there are no collection collection classes, only arrays, and arrays are strong. Here I use an array to wrap the collection into a

Reproduced:About the static link library (Lib,. A) with dynamic-link libraries (DLLs,. SO) (2011-10-10 21:04:26) reproduced Category: C, VC, CPP Under Windows, you can generally see files with the suffix dll and

This value : When the function executes, the This keyword does not point to the running function itself, but instead points to the object that called the function. So if you want to get a reference to the function itself inside the function, you can

Added some CRT functions with higher security in VC2005 CRT, such as strcpy_s and strncat_s. (MSDN: Significant enhancements have been made to make the CRT more secure. using CRT functions now have more secure versions. if a new secure function

When writing a DLL, use _ declspec (dllexport) to reduce the need to manually define which functions to export in the def file. Of course, if your dll contains all c ++ classes, you cannot specify the export function in def. Instead, you can use _

Let's look at the following code. Can you find out where the error is? Copy codeThe Code is as follows: Echo function_exists ('addcslashes'); // checks whether the function exists. Echo get_magic_quotes_gpc (). ''; // checks whether automatic

I. Function Classification C functions can be divided into three types: 1. Main function, that is, main function. Each program can have only one or more primary functions. No matter where the main function is written, C Programs always start to

Compare the similarities and differences between parameters with macros and functions From http://blog.csdn.net/piaojun_pj/article/details/5932639     The compiler processes Macros in the pre-compilation phase of the program. It mainly replaces