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In the previous article "Two examples explain how to delete commas and trailing slashes in strings in PHP" I introduced to you how to delete commas and trailing slashes in strings in PHP. Interested friends can go and learn about it~
This article will also explain the title "Usage of die() and sleep() functions in PHP" through examples.
1. About the usage of die() function
die() is a built-in function in PHP. It is used to print a message and exit the current php script. Equivalent to the exit() function in PHP.
The syntax is very simple, such as "die($message)
"
die() function only accepts one parameter, and it is not a parameter that must be passed.
The $message parameter indicates the message to be printed when exiting the script.
And note that die() has no return value, but prints the given message when exiting the script.
Note: This function is applicable to all PHP4 and above versions.
The example of using die function is as follows:
<?php $site = ""; fopen($site, "r") or die("无法连接到指定站点");
Output:
无法连接到给定站点
2. About the usage of sleep() function
sleep() is also a built-in function of PHP. It is used to delay the execution of a program for a given number of seconds.
The syntax is "int sleep(int $seconds)
";
This function also only accepts one parameter, and the parameter must be passed.
The $seconds parameter represents the delay time in seconds.
Return value: Return zero on success, return FALSE on error. If the call is interrupted by a signal, this function will return a non-zero value.
Note: This function generates E_WARNING when the number of seconds is negative, and this function is suitable for 4.
Usage example of sleep() function:
<?php // 初始时间 echo date('h:i:s') . "<br>"; // 暂停5秒 sleep(5); // 输出 echo date('h:i:s');
Output:
09:28:30 09:28:35
You can see that the time after pause (sleep) is 5 more than the time before pause (sleep) Second.
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