Home >Backend Development >PHP Tutorial >The difference between PHP magic variables __METHOD__, __FUNCTION__, functionmethod_PHP tutorial
The method name of the __METHOD__ class (newly added in PHP 5.0.0). Returns the name of the method as it was defined (case-sensitive).
__FUNCTION__ function name (newly added in PHP 4.3.0). Since PHP 5 this constant returns the name of the function as it was defined (case sensitive). In PHP 4 this value is always lowercase.
The documentation explanation all refers to the name of the return function (method). The difference is:
__FUNCTION__ just returns the name of the method;
__METHOD__ returns the name of the class and the name of the method.
<span> 1</span> <?<span>php </span><span> 2</span> <span>class</span><span> Test{ </span><span> 3</span> <span>public</span> <span>function</span><span> doit(){ </span><span> 4</span> <span>echo</span> <span>__FUNCTION__</span><span>; </span><span> 5</span> <span> } </span><span> 6</span> <span>public</span> <span>function</span><span> doitAgain(){ </span><span> 7</span> <span>echo</span> <span>__METHOD__</span><span>; </span><span> 8</span> <span> } </span><span> 9</span> <span> } </span><span>10</span> <span>$obj</span> = <span>new</span><span> Test(); </span><span>11</span> <span>$obj</span>-><span>doit(); </span><span>12</span> <span>echo</span> '<br>'<span>; </span><span>13</span> <span>$obj</span>-><span>doitAgain(); </span><span>14</span> ?>
The output result is:
doit
Test::doitAgain
__LINE__ The current line number in the file.
__FILE__ The full path and file name of the file. If used within an included file, returns the name of the included file. Since PHP 4.0.2, __FILE__ always contains an absolute path (or the resolved absolute path in the case of a symbolic link), whereas versions before that sometimes contained a relative path.
__DIR__ The directory where the file is located. If used within an included file, returns the directory where the included file is located. It is equivalent to dirname(__FILE__). Directory names do not include the trailing slash unless they are the root directory. (New in PHP 5.3.0) =
__FUNCTION__ function name (New in PHP 4.3.0). Since PHP 5 this constant returns the name of the function as it was defined (case sensitive). In PHP 4 this value is always lowercase.
__CLASS__ The name of the class (new in PHP 4.3.0). Since PHP 5 this constant returns the name of the class when it was defined (case sensitive). In PHP 4 this value is always lowercase.
__METHOD__ method name of class (newly added in PHP 5.0.0). Returns the name of the method as it was defined (case-sensitive).
__NAMESPACE__ The name of the current namespace (case sensitive). This constant is defined at compile time.
Magic variables refer to those that have different values according to different environments
For example,
__FILE__
is a typical magic variable. When it appears in the a.php file, its value is a. The specific path of php appears in the b.php file and is the specific path of b.php
Other magic variables include __FUNCTION__ and __CLASS__
In short, the values of these variables are often not fixed and change. Yes, it’s very magical, like magic, so it’s called a magic variable