A brief analysis of the difference between PHP static method and static variable

This article introduces the difference between static and static variables in PHP class, if the method is non-static, it is not necessary to use $this, that is, no non-static variable/method is called, of course, there is no problem in calling static variable/method. About the use of static and static methods in PHP . In PHP, there are two methods of accessing a class's Methods/variables: 1, creating the object $object = new Class (), and then using the call: $object->attribute/function, provided the variable/method is accessible. 2, directly call the class method/variable: class::attribute/function, either static/non-static can be. But there are prerequisites: a. If it is a variable, it needs to be accessible. B. If it is a method, in addition to the method can be accessed, but also need to satisfy: B1) If it is a static method, there is no special condition; b2) If the method is non-static, it is not necessary to use $this, that is, the non-static variable/method is not called, of course, there is no problem calling the static Then look at the use of $object-> and use class:: ... What is the difference: 1, use $object->., need to execute constructor to create object; 2, use class:: ... Call static method/variable, do not need to execute constructor to create object; 3, use class:: ... Call a non-static method/variable and do not need to execute the constructor to create the object. Since 2 and 3 are all the same, what is the point of static methods/variables? Difference: 1 static variable static members retain only one variable value, and this variable value is valid for all instances, that is, all instances share this member. 2 static method static method can directly use the class: ... Instead of static methods that require certain restrictions to use class::. Method calls, as described earlier.

