class

问题 Let's say I have a class like this (and also further assume that all the private variables: public class Item { private String _id = null; private String _name = null; private String _description = null; ... } Now, if I want to build a toString() representation of this class, I would do something like this inside the Item class: @Override public String toString() { return (_id + " " + _name + " " + _description); } But what if I have say 15 private variables inside the class? Do I have to

问题 I need to make a bunch of class variables and I would like to do it by looping through a list like that: vars=('tx','ty','tz') #plus plenty more class Foo(): for v in vars: setattr(no_idea_what_should_go_here,v,0) is it possible? I don't want to make them for an instance (using self in the __init__) but as class variables. 回答1: You can run the insertion code immediately after a class is created: class Foo(): ... vars=('tx', 'ty', 'tz') # plus plenty more for v in vars: setattr(Foo, v, 0) Also

问题 I accidentally found that the Clang compiler allows : inline class AAA { }; in C++. What's this? PS. I reported this to Clang mailing list cfe-dev@cs.uiuc.edu , and now waiting for reply. I'll update this question by I'm informed. 回答1: It's allowed in case you wish to declare a function that returns an object of that class directly after the class' declaration, for example : #include <iostream> inline class AAA { public: AAA() { // Nothing } AAA(const AAA& _Param) { std::cout << "Calling Copy

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: How to Deserialize XML document Suppose that I have a class that is defined like this in C#: public class Book { public string Title {get; set;} public string Subject {get; set;} public string Author {get; set;} } Suppose that I have XML that looks like this: <Book> <Title>The Lorax</Title> <Subject>Children's Literature</Subject> <Author>Theodor Seuss Geisel</Author> <Book> If I would like to instantiate an

问题 This has to be simple, but I can't seem to find an answer.... I have a generic stdClass object $foo with no properties. I want to add a new property $bar to it that's not already defined. If I do this: $foo = new StdClass(); $foo->bar = '1234'; PHP in strict mode complains. What is the proper way (outside of the class declaration) to add a property to an already instantiated object? NOTE: I want the solution to work with the generic PHP object of type stdClass. A little background on this

问题 This has to be simple, but I can't seem to find an answer.... I have a generic stdClass object $foo with no properties. I want to add a new property $bar to it that's not already defined. If I do this: $foo = new StdClass(); $foo->bar = '1234'; PHP in strict mode complains. What is the proper way (outside of the class declaration) to add a property to an already instantiated object? NOTE: I want the solution to work with the generic PHP object of type stdClass. A little background on this

问题 This has to be simple, but I can't seem to find an answer.... I have a generic stdClass object $foo with no properties. I want to add a new property $bar to it that's not already defined. If I do this: $foo = new StdClass(); $foo->bar = '1234'; PHP in strict mode complains. What is the proper way (outside of the class declaration) to add a property to an already instantiated object? NOTE: I want the solution to work with the generic PHP object of type stdClass. A little background on this

问题 So I am working on something that wasn't well thought out in the build from the backend team. That leaves me with a document full of divs. What I am doing is rolling back from the element I need to click on, get the parent container then find an element within the parent which has class="alert-box warn" , class="alert-box dead" , etc... Essentially, I'm trying to use multiple class selectors on each element. When I try to find just alert-box it doesn't seem to be working right. I'm assuming

问题 So I am working on something that wasn't well thought out in the build from the backend team. That leaves me with a document full of divs. What I am doing is rolling back from the element I need to click on, get the parent container then find an element within the parent which has class="alert-box warn" , class="alert-box dead" , etc... Essentially, I'm trying to use multiple class selectors on each element. When I try to find just alert-box it doesn't seem to be working right. I'm assuming

问题 What is the difference between sealed abstract and abstract Scala class? 回答1: The difference is that all subclasses of a sealed class (whether it's abstract or not) must be in the same file as the sealed class. 回答2: As answered, all directly inheriting subclasses of a sealed class (abstract or not) must be in the same file. A practical consequence of this is that the compiler can warn if the pattern match is incomplete. For instance: sealed abstract class Tree case class Node(left: Tree,