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using System.Net; ... string serverResponse; try { // Call a method that performs an HTTP request (per the above examples). serverResponse = PerformHttpRequest(); } catch (WebException ex) { if (ex.Status == WebExceptionStatus.ProtocolError) { HttpWebResponse...

A list can be rendered using the v-for directive. The syntax requires that you specify the source array to iterate on, and an alias that will be used to reference each item in the iteration. In the following example we use items as the source array, and item as the alias for each item. HTML <di...

<link rel="stylesheet" media="min-width: 600px" href="example.css" /> This stylesheet is still downloaded but is applied only on devices with screen width larger than 600px.

Common table expressions support extracting portions of larger queries. For example: WITH sales AS ( SELECT orders.ordered_at, orders.user_id, SUM(orders.amount) AS total FROM orders GROUP BY orders.ordered_at, orders.user_id ) SELECT sales.ordered_at, sales.total,...

Generate a random number between 0 and 1.0. (not including 1.0) Random rnd = new Random(); var randomDouble = rnd.NextDouble();

When creating Random instances with the same seed, the same numbers will be generated. int seed = 5; for (int i = 0; i < 2; i++) { Console.WriteLine("Random instance " + i); Random rnd = new Random(seed); for (int j = 0; j < 5; j++) { Console.Write(rnd.Next(...

Two Random class created at the same time will have the same seed value. Using System.Guid.NewGuid().GetHashCode() can get a different seed even in the same time. Random rnd1 = new Random(); Random rnd2 = new Random(); Console.WriteLine("First 5 random number in rnd1"); for (int i = 0...

The main methods that are useful with this class are popleft and appendleft from collections import deque d = deque([1, 2, 3]) p = d.popleft() # p = 1, d = deque([2, 3]) d.appendleft(5) # d = deque([5, 2, 3])

Average The AVG() aggregate function will return the average of values selected. SELECT AVG(Salary) FROM Employees Aggregate functions can also be combined with the where clause. SELECT AVG(Salary) FROM Employees where DepartmentId = 1 Aggregate functions can also be combined with group by ...

Include a row number according to the order specified. SELECT ROW_NUMBER() OVER(ORDER BY Fname ASC) AS RowNumber, Fname, LName FROM Employees

Uses a partition criteria to group the row numbering according to it. SELECT ROW_NUMBER() OVER(PARTITION BY DepartmentId ORDER BY DepartmentId ASC) AS RowNumber, DepartmentId, Fname, LName FROM Employees

This query selects all employees not on the Supervisors table. SELECT * FROM Employees WHERE EmployeeID not in (SELECT EmployeeID FROM Supervisors) The same results can be achieved using a LEFT JOIN. SELECT * FROM Employees AS e LEFT JOIN Supervisors AS s ON s.E...

Jasmine can spy on an existing function using the spyOn function. let calculator = { multiply: function(a, b) { return a * b; }, square: function(a) { return this.multiply(a, a); } } describe('calculator', function() { it('squares numbers by multiplying them by the...

Moment is a javascript library that was designed to make working with dates and times less time-consuming and more intuitive. You can easily start using this library by installing it in you web-app by using one of the following guides. Browser You can either download the JS file from the official...

If you're ever dealing with C Binary API's from Perl Code, via the syscall, ioctl, or fcntl functions, you need to know how to construct memory in a C Compatible way. For instance, if you were ever dealing with some function that expected a timespec, you'd look into /usr/include/time.h and find: s...

String literals imply no escaping or interpolation ( with the exception of quoting string terminators ) print 'This is a string literal\n'; # emits a literal \ and n to terminal print 'This literal contains a \'postraphe '; # emits the ' but not its preceding \ You can use alternative quoting...

Double-quoted strings use interpolation and escaping – unlike single-quoted strings. To double-quote a string, use either double quotes " or the qq operator. my $greeting = "Hello!\n"; print $greeting; # => Hello! (followed by a linefeed) my $bush = "They misunderestimat...

In Haskell, data types can have arguments just like functions. Take the Maybe type for example. Maybe is a very useful type which allows us to represent the idea of failure, or the possiblity thereof. In other words, if there is a possibility that a computation will fail, we use the Maybe type ther...

The publisher-subscriber is a familiar concept given the rise of YouTube, Facebook and other social media services. The basic concept is that there is a Publisher who generates content and a Subscriber who consumes content. Whenever the Publisher generates content, each Subscriber is notified. Subsc...

Step 1. Install Java 7 or 8 Step 2. Download Apache Kafka at: http://kafka.apache.org/downloads.html For example, we will try download Apache Kafka 0.10.0.0 Step 3. Extract the compressed file. On Linux: tar -xzf kafka_2.11-0.10.0.0.tgz On Window: Right click --> Extract here Step 4. Sta...