


How PHP determines the source of mobile devices
In today’s era when mobile devices are so popular, we may often need to use page matching for mobile devices when doing web front-end development . Of course, we can use responsive page design to handle the front-end matching problem, but the responsive page just does not display certain codes, but it will still be loaded into the user's mobile device. In order to better take care of the user's mobile browsing experience and reduce unnecessary loading. We can then use PHP to reduce the user's code loading and improve the user's experience when browsing the page. Since there are now many types of mobile devices and various browsers, simply judging by User-Agent cannot completely solve the problem.
function isMobile()
{
// If there is HTTP_X_WAP_PROFILE, it must be a mobile device
if (isset ($_SERVER['HTTP_X_WAP_PROFILE']))
{
return true;
}
// If the via information contains wap, it must be a mobile device, and some service providers will block this information
if (isset ($_SERVER['HTTP_VIA']))
{
// If not found, it is false, otherwise it is true
return stristr($_SERVER['HTTP_VIA'], "wap") ? true : false;
}
// Determine the client flag sent by the mobile phone, compatibility needs to be improved
if (isset ($_SERVER['HTTP_USER_AGENT']))
{
$clientkeywords = array ('nokia',
'sony',
'ericsson',
'mot',
'samsung',
'htc',
'sgh',
'lg',
'sharp',
'sie-',
'philips',
'panasonic',
'alcatel',
'lenovo',
'iphone',
'ipod',
'blackberry',
'meizu',
'android',
'netfront',
'symbian',
'ucweb',
'windowsce',
'palm',
'operamini',
'operamobi',
'openwave',
'nexusone',
'cldc',
'midp',
'wap',
'mobile'
);
// Find keywords for mobile browsers from HTTP_USER_AGENT
if (preg_match("/(" . implode('|', $clientkeywords) . ")/i", strtolower($_SERVER['HTTP_USER_AGENT'])))
{
return true;
} }
}
// Agreement method, because it may be inaccurate, leave it to the final judgment
if (isset ($_SERVER['HTTP_ACCEPT']))
{
// If it only supports wml and does not support html, it must be a mobile device
// If wml and html are supported but wml comes before html, it is a mobile device
if ((strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') !== false) && (strpos($_SERVER['HTTP_ACCEPT'], 'text/html') === false || (strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml')
{
return true;
} }
}
return false;
}
?>
Currently this method can be used for most mobile device judgments. When using it, you can also add some UA judgment parameters as needed.

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。

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。

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。

在php中,可以使用substr()函数来读取字符串后几个字符,只需要将该函数的第二个参数设置为负值,第三个参数省略即可;语法为“substr(字符串,-n)”,表示读取从字符串结尾处向前数第n个字符开始,直到字符串结尾的全部字符。

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。


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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
