methods

问题 I noticed that if I define a class attribute equal to a function when I create an instance of that class the attribute becomes a bound method. Can someone explain me the reason of this behaviour? In [9]: def func(): ...: pass ...: In [10]: class A(object): ....: f = func ....: In [11]: a = A() In [12]: a.f Out[12]: <bound method A.func of <__main__.A object at 0x104add190>> In [13]: a.f() --------------------------------------------------------------------------- TypeError Traceback (most

问题 Can someone please explain to me the difference between methods and events in the ASP.NET page life cycle? Thanks 回答1: When a page runs a series of methods are executed. These methods in turn raise events that can be handled by the user to perform various tasks like initializing controls, populating control properties, executing control behavioral code, etc. Here is an excellent flowchart from MSDN that shows the different methods that are executed, and the events that are raised from those

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: How to check if a number is a power of 2 How could I write a method that would return true if passed in the value 2, 4, 8, 32, 64, and so on? 回答1: This is probably the best way: ((value & -value) == value) 回答2: Might want to look at this if you need a fast algorithm: http://en.wikipedia.org/wiki/Power_of_two#Fast_algorithm_to_check_if_a_positive_number_is_a_power_of_two 来源： https://stackoverflow.com/questions

问题 I'm failing to understand the correlation between routes, controllers, and views (and how they connect to each other). So, I've got my controller with the index , show , new , create , destroy methods. And the corresponding GET /entries(.:format) entries#index POST /entries(.:format) entries#create GET /entries/new(.:format) entries#new GET /entries/:id/edit(.:format) entries#edit GET /entries/:id(.:format) entries#show PUT /entries/:id(.:format) entries#update DELETE /entries/:id(.:format)

问题 I want to build a custom method Array#drop_every(n) (I know it's monkey patching, I am doing this for a homework), which returns a new array omitting every nth element: [4, 8, 15, 16, 23, 42].drop_every(2) # [4, 15, 23] I want to implement it with Array#delete_if , but by referring to the index and not to the element itself, (similar to each_index ) something like this: def drop_every(step) self.delete_if { |index| index % step == 0 } end How do I do this? I don't insist on using delete_if ,

问题 I'm trying to implement method chaining in C++, which turns out to be quite easy if the constructor call of a class is a separate statement, e.g: Foo foo; foo.bar().baz(); But as soon as the constructor call becomes part of the method chain, the compiler complains about expecting ";" in place of "." immediately after the constructor call: Foo foo().bar().baz(); I'm wondering now if this is actually possible in C++. Here is my test class: class Foo { public: Foo() { } Foo& bar() { return *this

问题 This question already has answers here : Does Java support default parameter values? (20 answers) Closed 6 years ago . Is it possible to set the default method parameter values in Java? Example: If there is a method public int doSomething(int arg1, int arg2) { //some logic here return 0; } is it possible to modify the given method in order to be able to call it with and without parameters? example: doSomething(param1, param2); doSomething(); Thanks! 回答1: You can accomplish this via method

问题 I have a module of following module SimpleTask def task1 end def task2 end def task3 end end And I have a model which requires only task2 method of module SimpleTask . I know including SimpleTask in my model with include SimpleTask would do the job. But I wonder if I can only include specific task2 method in my model. 回答1: It sounds like you need to refactor #task2 into a separate module (e.g., BaseTask ). Then you can easily include only BaseTask where you only need #task2 . module BaseTask

问题 I found this thread: How to change annotation value at runtime using reflection? And I'm trying to change method annotation, but java.lang.reflect.Method does not contain any map-field like "annotations" or method like "getDeclaredAnnotationMap" There is only private byte[] annotations but what can I do with this byte array? So, how to modify annotation of method? EDIT: I created that: http://pastebin.com/T2rewcwU But that only edit this instance of method, if you uncomment 33 line of code

问题 This is an attempt to understand a portion of ITEM 40: Design Method Signatures Carefully from Effective Java 2nd Edition. One of the things suggested to improve method signature readability is to aim for four or fewer parameters. It is suggested that longer parameter lists be managed by using a variety of techniques one of which is as follows : A third technique that combines aspects of the first two is to adapt the Builder pattern (Item 2) from object construction to method invocation. If