How to create an object property from a variable value in JavaScript? [duplicate]
There’s the dot notation and the bracket notation myObj[a] = b;
properties
Property initialization using “by lazy” vs. “lateinit”
Here are the significant differences between lateinit var and by lazy { … } delegated property: lazy { … } delegate can only be used for val properties, whereas lateinit can only be applied to vars, because it can’t be compiled to a final field, thus no immutability can be guaranteed; lateinit var has a … Read more
What is the difference between properties and attributes in HTML?
When writing HTML source code, you can define attributes on your HTML elements. Then, once the browser parses your code, a corresponding DOM node will be created. This node is an object, and therefore it has properties. For instance, this HTML element: <input type=”text” value=”Name:”> has 2 attributes (type and value). Once the browser parses … Read more
How to use a variable for a key in a JavaScript object literal?
{ thetop : 10 } is a valid object literal. The code will create an object with a property named thetop that has a value of 10. Both the following are the same: obj = { thetop : 10 }; obj = { “thetop” : 10 }; In ES5 and earlier, you cannot use a … Read more
@synthesize vs @dynamic, what are the differences?
@synthesize will generate getter and setter methods for your property. @dynamic just tells the compiler that the getter and setter methods are implemented not by the class itself but somewhere else (like the superclass or will be provided at runtime). Uses for @dynamic are e.g. with subclasses of NSManagedObject (CoreData) or when you want to … Read more
How do I enumerate the properties of a JavaScript object? [duplicate]
Simple enough: for(var propertyName in myObject) { // propertyName is what you want // you can get the value like this: myObject[propertyName] } Now, you will not get private variables this way because they are not available. EDIT: @bitwiseplatypus is correct that unless you use the hasOwnProperty() method, you will get properties that are inherited … Read more
How to get the list of properties of a class?
Reflection; for an instance: obj.GetType().GetProperties(); for a type: typeof(Foo).GetProperties(); for example: class Foo { public int A {get;set;} public string B {get;set;} } … Foo foo = new Foo {A = 1, B = “abc”}; foreach(var prop in foo.GetType().GetProperties()) { Console.WriteLine(“{0}={1}”, prop.Name, prop.GetValue(foo, null)); } Following feedback… To get the value of static properties, pass … Read more
Using @property versus getters and setters
Prefer properties. It’s what they’re there for. The reason is that all attributes are public in Python. Starting names with an underscore or two is just a warning that the given attribute is an implementation detail that may not stay the same in future versions of the code. It doesn’t prevent you from actually getting … Read more
Test for existence of nested JavaScript object key
You have to do it step by step if you don’t want a TypeError because if one of the members is null or undefined, and you try to access a member, an exception will be thrown. You can either simply catch the exception, or make a function to test the existence of multiple levels, something … Read more
Does C# have extension properties?
For the moment it is still not supported out of the box by Roslyn compiler … Until now, the extension properties were not seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have seen this as proposal champion but it wasn’t released yet, most of … Read more