Why do we need static classes? ? ? ? ? ? ? ?
--------Static variables or functions are saved in static memory, only It will not be released until the end of the program, so when is it assigned?
It is during compilation. Dynamic classes are dynamically allocated when the program is running. (Recommended learning: PHP Programming from entry to proficiency)
If called once in a class, the static class needs to do more work when compiling, and the dynamic class needs to do more work when executing Do more work, but PHP is a dynamic language, and these two steps are not lost every time, so for a class that only runs once, it doesn't matter who is faster and who is slower.
But it is different if a class is called multiple times in the program. The static class is assigned a value when it is compiled, and can be called directly during subsequent runs of the program without Dynamically allocating memory saves time, which is why static classes are faster than dynamic classes (provided that they are called multiple times and remembered).
Static methods do not need to instantiate objects and can be called directly through the class name. The operator is a double colon::
Car::getName();
First of all: the class cannot be marked static, nor That is to say, there is no "static class"!
The so-called "static class" refers to: the class containing static members and methods are marked with static. For example:
<?php class Math { public static function ceil($value) { return ceil($value); } public static function floor($value) { return floor($value); } } ?>
Other types of static methods can be used without instantiating them into objects. Instantiation will report an error;
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