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The Page directive defines the attributes specific to the page file for the page parser and the compiler. The basic syntax of Page directive is: <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Trace="tr...
The OutputCache directive controls the output caching policies of a web page or a user control. The basic syntax of OutputCache directive is: <%@ OutputCache Duration="15" VaryByParam="None" %>
This example show how you can check if a service already exists (i.e., is installed on the machine) or not. This code requires only the lowest privileges necessary, so each process can perform the check, no matter what level of security it is running at. #define UNICODE #define _UNICODE #include ...
>>> '{0:.0f}'.format(42.12345) '42' >>> '{0:.1f}'.format(42.12345) '42.1' >>> '{0:.3f}'.format(42.12345) '42.123' >>> '{0:.5f}'.format(42.12345) '42.12345' >>> '{0:.7f}'.format(42.12345) '42.1234500' Same hold for other way of referenc...
You can also use regular expressions to split a string. For example, import re data = re.split(r'\s+', 'James 94 Samantha 417 Scarlett 74') print( data ) # Output: ['James', '94', 'Samantha', '417', 'Scarlett', '74']
You can get rid of manage.py and use the django-admin command instead. To do so, you will have to manually do what manage.py does: Add your project path to your PYTHONPATH Set the DJANGO_SETTINGS_MODULE export PYTHONPATH="/home/me/path/to/your_project" export DJANGO_SETTINGS_MODULE...
IList<T> is never a subtype of a different IList<T1>. IList is invariant in its type parameter. class Animal { /* ... */ } class Dog : Animal { /* ... */ } IList<Dog> dogs = new List<Dog>(); IList<Animal> animals = dogs; // type error There is no subtype relat...
If you have a vsix file, you can install it by running the file. Get the vsix file (this is the extension installer) Run the file. In the window that opens, confirm the installation.
In Visual studio go to Tools > Extensions and updates... In the window that opens go to online Select Visual Studio Gallery You can search for an extension on the search box at the upper right corner Select the extension you want to add Click on download. Once download is complete, click...
By default, Django renders ForeignKey fields as a <select> input. This can cause pages to be load really slowly if you have thousands or tens of thousand entries in the referenced table. And even if you have only hundreds of entries, it is quite uncomfortable to look for a particular entry amo...
Using threading & queue: from socket import socket, AF_INET, SOCK_STREAM from threading import Thread from queue import Queue def echo_server(addr, nworkers): print('Echo server running at', addr) # Launch the client workers q = Queue() for n in range(nworkers): ...
Interfaces may have variant type parameters. interface IEnumerable<out T> { // ... } interface IComparer<in T> { // ... } but classes and structures may not class BadClass<in T1, out T2> // not allowed { } struct BadStruct<in T1, out T2> // not allo...
Introduced in Java 8, default methods are a way of specifying an implementation inside an interface. This could be used to avoid the typical "Base" or "Abstract" class by providing a partial implementation of an interface, and restricting the subclasses hierarchy. Observer patte...
In a non-strict-mode scope, when a variable is assigned without being initialized with the var, const or the let keyword, it is automatically declared in the global scope: a = 12; console.log(a); // 12 In strict mode however, any access to an undeclared variable will throw a reference error: &...
Differences in subsetting syntax A data.table is one of several two-dimensional data structures available in R, besides data.frame, matrix and (2D) array. All of these classes use a very similar but not identical syntax for subsetting, the A[rows, cols] schema. Consider the following data stored i...
Delegates may have variant type parameters. delegate void Action<in T>(T t); // T is an input delegate T Func<out T>(); // T is an output delegate T2 Func<in T1, out T2>(); // T1 is an input, T2 is an output This follows from the Liskov Substitution Principle, w...
Category theory is a modern mathematical theory and a branch of abstract algebra focused on the nature of connectedness and relation. It is useful for giving solid foundations and common language to many highly reusable programming abstractions. Haskell uses Category theory as inspiration for some o...
A category C consists of: A collection of objects called Obj(C) ; A collection (called Hom(C)) of morphisms between those objects. If a and b are in Obj(C), then a morphism f in Hom(C) is typically denoted f : a -> b, and the collection of all morphism between a and b is denoted hom(a,b) ; A...
Using Kestrel you can specify port using next approaches: Defining ASPNETCORE_URLS environment variable. Windows SET ASPNETCORE_URLS=https://0.0.0.0:5001 OS X export ASPNETCORE_URLS=https://0.0.0.0:5001 Via command line passing --server.urls parameter dotnet run --server.urls=http...
If you have a string that contains Python literals, such as strings, floats etc, you can use ast.literal_eval to evaluate its value instead of eval. This has the added feature of allowing only certain syntax. >>> import ast >>> code = """(1, 2, {'foo': 'bar'})&quot...

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