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What are external variables of PHP constants and variables? Will you use it? How many other constants do you know?
What are external variables of PHP constants and variables? Will you use it? How many other constants do you know?
The previous article introduced you to "Do you know PHP constants and variables? How to use it? ? ? 》, this article continues to introduce PHP constants and external variables to you, follow my steps and start together! ! !
##External variables of PHP constants and variables:
External variables: External variables are some variables specified by PHP during use;
<html>
<head>
</head>
<body>
<form action="" method="get">
<input type="text" name="username"/>
<input type="password" name="pwd"/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
get method. reg.php accepts the two values of username and password passed by the user;
first external variable: $_GET
$ The main function of _GET is to get the data passed by the value;
<html>
<head>
</head>
<body>
<form action="" method="get">
<input type="text" name="username"/>
<input type="password" name="pwd"/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
的值
var_dump($_GET['username']);
?>
PHP code:
<html>
<head>
</head>
<body>
<form action="" method="post">
<input type="text" name="username"/>
<input type="password" name="pwd"/>
<input type="submit" value="提交"/>
</form>
</body>
</html>
<?php
//$_POST后面加上中括号，将username作为字符串放在中括号里面，
//就得到了表单里面的<input type="text" name="username"/>的值
var_dump($_POST['pwd']);
?>
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