A brief analysis of the difference between php static methods and static variables

About the usage ofphp static methods and static variables.

In PHP, there are two ways to access class methods/variables: 1. Create the object $object = new Class(), and then use "->" to call: $object->attribute/function, provided that the variable/method is accessible. 2. Directly call class methods/variables: class::attribute/function, whether it is static or non-static. But there are prerequisites: A. If it is a variable, the variable needs to be accessible. B. If it is a method, in addition to the method being accessible, it also needs to meet: b1) If it is a static method, there are no special conditions; b2) If it is a non-static method, it needs to be changed not to use $this in the method, that is, no non-static variables/methods are called. Of course, there is no problem in calling static variables/methods.

Let’s look at the difference between using $object->... and using class::...:

Since 2 and 3 are the same, what’s the point of static methods/variables existing? difference: 1. Static variables Static members only retain one variable value, and this variable value is valid for all instances, that is, all instances share this member. 2. Static method Static methods can be called directly using class::..., while non-static methods need to meet certain restrictions before they can be called using class::.. methods, as mentioned before.