


First clarify the output order of PHP
1. Turn on the php output cache: echo,print -> php output_buffring -> server buffering -> browser buffering -> browser display
2. PHP output cache is not turned on: echo,print -> server buffering -> browser buffering -> browser display
Also make it clear The browser's output cache: 256Bytes for IE, 1000Bytes for Chrome and FireFox. Only when the output data reaches this length or the script ends, the browser will output the data on the page
Let’s talk about the use Several PHP settings and APIs:
1.output_buffering configuration in php.ini
•Off: means turning off the PHP output cache
•On: turning on the infinite output cache
• 4096: Open the output cache with a size of 4096 Byte
2.php.ini in the implicit_flush configuration
•On: Indicates that flush is automatically called after each output (such as echo, print) () function, directly output
•Off: Contrary to On, flush() will not be called after each output, and it will not be output until the server buffering is full, but we can use the flush() function instead. It doesn’t matter if it is turned on, it is more flexible
3.ob_flush() function: Take out the data in PHP buffering and put it into server buffering
4.flush() function: Take out Server buffering The data is put into browser buffering
5.ob_start() function: I don’t know much about this function now, because the output will not be clear after it is turned on. Controlled by ob_flush(), even if ob_flush() and flush() are used, the data cannot be output immediately on the browser. What is known now is that if output_buffering=Off, even if ob_start() is used, the output data cannot be cached , and if output_buffering=On, even if ob_start() is not used, the output data can be cached by PHP, so I think ob_start is relatively useless, so I will ignore it for the time being
Then let’s look at the code (setting output_buffering= 4096,implicit_flush=Off)
,1000); //IE cache 256Bytes
echo str_repeat(' ', 1000); Save it instead of directly outputting
for($i=0;$i echo $i.'
';
ob_flush();
flush();
sleep(1);
}
?>
html>
The output result of the code here is output line by line. For the specific principle, please refer to the efficacy of the ob_flush() and flush() functions.
If any of these two functions is missing, under my setting, it will wait until 0 , 1, 2, 3, 4 are all cached and then output together
Finally, I quote a paragraph from Laruence’s blog, I hope it will be helpful to everyone’s understanding
The description of ob_flush/flush in the manual is to refresh the output buffer, and it also needs to be used in conjunction, so it will cause confusion to many people...
Actually, they operate on different objects. In some cases, flush does nothing at all..
The ob_* series of functions operate the output buffer of PHP itself.
So, ob_flush is to refresh PHP's own buffer.
Strictly speaking, flush only has an actual effect when PHP is installed as an apache Module (handler or filter). It refreshes the buffer of the WebServer (which can be considered specifically apache).
Under the sapi of apache module, flush will indirectly call the apache api by calling the flush member function pointer of sapi_module: ap_rflush refreshes the output buffer of apache. Of course, the manual also says that there are some other modules of apache. It may change the result of this action..
1. Some Apache modules, such as mod_gzip, may perform output caching by themselves,
2. This will cause the results generated by the flush() function to not be immediately cached. Sent to client browser.
3.
4. Even the browser will cache the received content before displaying it. For example, Netscape
5. The browser will cache the content until it receives a newline or the beginning of the html tag, and the entire table will not be displayed until
6. it receives the tag.
7.
8. Some versions of Microsoft Internet Explorer will only start displaying the page after receiving 256
9. bytes, so some extra spaces must be sent to make this
10. Some browsers display page content.
So, the correct order of using the two is. First ob_flush, then flush,
Of course, under other sapi, you can not call flush, just to ensure that your code For portability, it is recommended to use it together.

php把负数转为正整数的方法:1、使用abs()函数将负数转为正数,使用intval()函数对正数取整,转为正整数,语法“intval(abs($number))”;2、利用“~”位运算符将负数取反加一,语法“~$number + 1”。

实现方法:1、使用“sleep(延迟秒数)”语句,可延迟执行函数若干秒;2、使用“time_nanosleep(延迟秒数,延迟纳秒数)”语句,可延迟执行函数若干秒和纳秒;3、使用“time_sleep_until(time()+7)”语句。

php除以100保留两位小数的方法:1、利用“/”运算符进行除法运算,语法“数值 / 100”;2、使用“number_format(除法结果, 2)”或“sprintf("%.2f",除法结果)”语句进行四舍五入的处理值,并保留两位小数。

判断方法:1、使用“strtotime("年-月-日")”语句将给定的年月日转换为时间戳格式;2、用“date("z",时间戳)+1”语句计算指定时间戳是一年的第几天。date()返回的天数是从0开始计算的,因此真实天数需要在此基础上加1。

php判断有没有小数点的方法:1、使用“strpos(数字字符串,'.')”语法,如果返回小数点在字符串中第一次出现的位置,则有小数点;2、使用“strrpos(数字字符串,'.')”语句,如果返回小数点在字符串中最后一次出现的位置,则有。

方法:1、用“str_replace(" ","其他字符",$str)”语句,可将nbsp符替换为其他字符;2、用“preg_replace("/(\s|\ \;||\xc2\xa0)/","其他字符",$str)”语句。

php字符串有下标。在PHP中,下标不仅可以应用于数组和对象,还可应用于字符串,利用字符串的下标和中括号“[]”可以访问指定索引位置的字符,并对该字符进行读写,语法“字符串名[下标值]”;字符串的下标值(索引值)只能是整数类型,起始值为0。

在PHP中,可以利用implode()函数的第一个参数来设置没有分隔符,该函数的第一个参数用于规定数组元素之间放置的内容,默认是空字符串,也可将第一个参数设置为空,语法为“implode(数组)”或者“implode("",数组)”。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

Atom editor mac version download
The most popular open source editor

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

Dreamweaver CS6
Visual web development tools
