accessor

问题 I am trying to understand accessors & mutators and why I need them. And my another ask is the middle part of an attribute's method for an example: Accessor : public function getFirstNameAttribute($value) { return ucfirst($value); } Mutator: public function setFirstNameAttribute($value) { $this->attributes['first_name'] = strtolower($value); } Here, we can see getFirstNameAttribute and setFirstNameAttribute methods and I haven't been able to clear the middle part FirstName of them. I will

问题 I am currently trying to learn C++ and following an instruction. I've researched on mutators and accessors but I need a simple explanation. class Customer { public: Customer(); ~Customer(); private: string m_name; int m_age; }; Right the code above is in a header file. Within the instructions it is asking me to set a public accessors and mutator for both data. How do I do this? Also it mentions checking the age is not negative in the mutator. I know how to implement the code but I'm just

问题 I learned c# recently, so when I learned to write properties, I was taught to do it like this: public string Name { get; set; } Auto properties are great! But now I'm trying to do something a little more complicated, so I need to write a custom pair of accessors. private string _Name; public string Name { get { return _Name; } set { _Name = value } } I know the compiler makes a private instance variable down in it's murky depths when one uses autos, but I'm spoiled and don't want that private

问题 One of the functionalities of my bot is handling a Shopping Cart. The user can add items anywhere in the conversation and then finish shopping to close the product cart. To avoid passing the cart from dialog to dialog I would like to create a UserProfile property in the UserState (The UserProfile property has a ShoppingCart attribute) but I don't quite know how to use this properly. My Main Dialog contains a set of Child Dialogs and some of them need to be able to access the ShoppingCart

问题 I have an accessor function that returns a const reference to a type (std::map) ... ... myMap_t const& getMap() const {return paramMap;} The type has an overloaded [] operator. What is the syntax to then use the [] operator directly from the getter function in a way like the following, but that actually works. parameter = contextObj.getMap()[key]; Error message is: context.cpp:35: error: passing 'const std::map< std::basic_string<char, std::char_traits<char>, std::allocator<char> >, float,

问题 I have an accessor function that returns a const reference to a type (std::map) ... ... myMap_t const& getMap() const {return paramMap;} The type has an overloaded [] operator. What is the syntax to then use the [] operator directly from the getter function in a way like the following, but that actually works. parameter = contextObj.getMap()[key]; Error message is: context.cpp:35: error: passing 'const std::map< std::basic_string<char, std::char_traits<char>, std::allocator<char> >, float,

问题 Does the following code call an accessor "set" function or does it modify the pointer myMember directly? aClass.h @interface MyClass : NSObject { NSArray *myMember; } @property (nonatomic, retain) NSArray *myMember; aClass.c @implementation GameplayScene @synthesize myMember; - (id) init { if ( (self = [super init]) ) { myMember = [NSArray array]; } } In other words, I would like to know if the method setMyMember is being called, or if the pointer of myMember is being modified directly.

问题 Once you have loaded a component are you then able to access properties of that object with set conditions? For instance, if you have a one-to-many relationship between people and pets, you load people specifying a particular person, you then want to pull all said persons pets where the pets are of a particular species. cats vs dogs for instance. <cfset person=EntityLoad("person", {name="#URL.name#"})> <cfset pets=person[1].getPets()> is there anyway to call getPets where type='dog' or

问题 Unless I am thoroughly mistaken, the getter/setter pattern is a common pattern used for two things: To make a private variable so that it can be used, but never modified, by only providing a getVariable method (or, more rarely, only modifiable, by only providing a setVariable method). To make sure that, in the future, if you happen to have a problem to which a good solution would be simply to treat the variable before it goes in and/or out of the class, you can treat the variable by using an

问题 In objective c, if the using the getter and directly accessing the ivar do exactly the same thing, no lazy loading code in the getter, all it does is returns the ivar, would you still use the accessor or access the ivar directly since there is no difference? Why? EDIT: I'm talking about inside the class. 回答1: There is a small performance advantage to be enjoyed by using the ivar directly. However, to avoid confusion, I typically prefix my ivars with _ on the front, and then synthesize a