methods

问题 Is it possible to have class A with an empty method say render() .. then you create 3 instances of the class, so you have objects b, c, d , so can I THEN assign bodies for the render method for each object? Here's an example, in JavaScript you can have an object say a and then anywhere you can say a.method = function() { /* do something */ } After that line, you will have a method with the name method for the object a and whenever called it will /* do something */ . Is this possible in Java

问题 Hello everyone my name is Fyree, and I'm having problems with a school assignment where I need to create a method that takes the values from the user, and puts then through the computeRate() method to print out a line that shows the computed Rate. Since the program is taking the user input values as Strings, I am unable to use that in the compute rate formula since they are not ints. My problem is being able to convert the Strings into ints, and having the computeRate() be able to correctly

问题 I was trying to override __str__ and __repr__ for class as shown in the code below. The new methods are called whenever I call the instance_method but the object calls for class_method remains the same (Please see the code snippet and the output below for clarity). Is there a way possible to override __str__ and __repr__ for @classmethod so that the value of cls can be changed? I have also tried adding __str__ and __repr__ as @classmethod but nothing changed. class Abc: def __init__(self,

问题 I'm currently working on a project where I'm using a singleton class to change the view for the user. This DisplayManager (the singleton) has methods like addView(View view) and replaceView(View view) . But it also has a method called displayRootView() which may only be called once (during init) and by only 1 class, i.e. the StartUp class that extends the Application class. Any idea as to how I can prevent other classes who use the singleton from calling the displayRootView() method? I

问题 How (actual with which instuments like ReSharper) in VS10 developer can find "unsafe" method invokes - i.e. invokes, which unattainable by call stack in no one safe block (try-catch) ? class A { public static vois f() { try { ... B.DoSome(); // safe call, exceptions handled } catch(Exception e) { ... } } public static void f2() { ... //no try-catch block B.DoSome(); // possible unhandled exception } } class B { public static void DoSome() { ... //no try-catch block, possible to raise

问题 I would like to create a function that deals with missing values. However, when I tried to specify the missing type Array{Missing, 1}, it errors. function f(x::Array{<:Number, 1}) # do something complicated println("no missings.") println(sum(x)) end function f(x::Array{Missing, 1}) x = collect(skipmissing(x)) # do something complicated println("removed missings.") f(x) end f([2, 3, 5]) f([2, 3, 5, missing]) I understand that my type is not Missing but Array{Union{Missing, Int64},1} When I

问题 I want to override a method in the System.Resources.ResourceManager class in mscorlib v4. I want to override the method GetResourceFileName like this; protected override string GetResourceFileName(CultureInfo culture) { string resourceFileName = base.GetResourceFileName(culture); return resourceFileName.Replace(".resources", ".resx"); } The problem is, to instanciate a ResourceManager class I must use the static method CreateFileBasedResourceManager, which returns a new instance of the

问题 Sorry for the incredibly newbie question, but I can see myself drifting into bad practices if I don't ask. I have a PHP method that I want to return all the values of a given database column, in order to place the contents in a dropdown menu for a HTML form. I could obviously construct the whole HTML in the PHP method and return that as a string, but I imagine this is pretty bad practice. Since PHP methods can only return one value, I imagine I'll need to call the method several times to

问题 i need to have several functions in cakephp application (for some regular expression matching). which is best way to store them, so i can access to them in every controller action? tnx in adv! 回答1: I would recommend you store the functions in the AppController class. All of your controller classes inherit from this controller. Also create the app_controller.php file in the root folder of your application if you have not already. 回答2: Or, if the actions aren't typical controller actions - you

问题 I would like to List all orders that contain products that had discounts on them, so I can generate a report based on only the orders that have discounts on them and get the [ order number, order date, order status, order total, user name, email and phone ] of every order that have product with discount something like if (order_had_product_with_discount) { get the [ order number, order date, order status, order total, user name, email and phone ] of this order } It's not valid code but I need