Tutorial by Examples: d

The Switch statement works very well with Enum values enum CarModel { case Standard, Fast, VeryFast } let car = CarModel.Standard switch car { case .Standard: print("Standard") case .Fast: print("Fast") case .VeryFast: print("VeryFast") } Since we ...

Ansible can be installed on CentOS or other Red Hat based systems. Firstly you should install the prerequisites: sudo yum -y update sudo yum -y install gcc libffi-devel openssl-devel python-pip python-devel then install Ansible with pip: sudo pip install ansible I can recommend for you to u...

To duplicate a table, simply do the following: CREATE TABLE newtable LIKE oldtable; INSERT newtable SELECT * FROM oldtable;

WITH CTE (StudentId, Fname, LName, DOB, RowCnt) as ( SELECT StudentId, FirstName, LastName, DateOfBirth as DOB, SUM(1) OVER (Partition By FirstName, LastName, DateOfBirth) as RowCnt FROM tblStudent ) SELECT * from CTE where RowCnt > 1 ORDER BY DOB, LName This example uses a Common Table ...

// Calculate what day of the week is 36 days from this instant. System.DateTime today = System.DateTime.Now; System.TimeSpan duration = new System.TimeSpan(36, 0, 0, 0); System.DateTime answer = today.Add(duration); System.Console.WriteLine("{0:dddd}", answer);

Add days into a dateTime object. DateTime today = DateTime.Now; DateTime answer = today.AddDays(36); Console.WriteLine("Today: {0:dddd}", today); Console.WriteLine("36 days from today: {0:dddd}", answer); You also can subtract days passing a negative value: DateTime today...

double[] hours = {.08333, .16667, .25, .33333, .5, .66667, 1, 2, 29, 30, 31, 90, 365}; DateTime dateValue = new DateTime(2009, 3, 1, 12, 0, 0); foreach (double hour in hours) Console.WriteLine("{0} + {1} hour(s) = {2}", dateValue, hour, ...

string dateFormat = "MM/dd/yyyy hh:mm:ss.fffffff"; DateTime date1 = new DateTime(2010, 9, 8, 16, 0, 0); Console.WriteLine("Original date: {0} ({1:N0} ticks)\n", date1.ToString(dateFormat), date1.Ticks); DateTime date2 = date1.AddMilliseconds(1); Console....

DateTime date1 = new DateTime(2009, 8, 1, 0, 0, 0); DateTime date2 = new DateTime(2009, 8, 1, 12, 0, 0); int result = DateTime.Compare(date1, date2); string relationship; if (result < 0) relationship = "is earlier than"; else if (result == 0) relationship = "is the...

const int July = 7; const int Feb = 2; int daysInJuly = System.DateTime.DaysInMonth(2001, July); Console.WriteLine(daysInJuly); // daysInFeb gets 28 because the year 1998 was not a leap year. int daysInFeb = System.DateTime.DaysInMonth(1998, Feb); Console.WriteLine(daysInFeb); // daysIn...

Add years on the dateTime object: DateTime baseDate = new DateTime(2000, 2, 29); Console.WriteLine("Base Date: {0:d}\n", baseDate); // Show dates of previous fifteen years. for (int ctr = -1; ctr >= -15; ctr--) Console.WriteLine("{0,2} year(s) ago:{1:d}", ...

Once the instance of the BackgroundWorker has been declared, it must be given properties and event handlers for the tasks it performs. /* This is the backgroundworker's "DoWork" event handler. This method is what will contain all the work you wish to have your progra...

This allows the BackgroundWorker to be cancelled in between tasks bgWorker.WorkerSupportsCancellation = true; This allows the worker to report progress between completion of tasks... bgWorker.WorkerReportsProgress = true; //this must also be used in conjunction with the ProgressChanged event...

A BackgroundWorker is commonly used to perform tasks, sometimes time consuming, without blocking the UI thread. // BackgroundWorker is part of the ComponentModel namespace. using System.ComponentModel; namespace BGWorkerExample { public partial class ExampleForm : Form { ...

The following example demonstrates the use of a BackgroundWorker to update a WinForms ProgressBar. The backgroundWorker will update the value of the progress bar without blocking the UI thread, thus showing a reactive UI while work is done in the background. namespace BgWorkerExample { public...

Properties can be added with categories using associated objects, a feature of the Objective-C runtime. Note that the property declaration of retain, nonatomic matches the last argument to objc_setAssociatedObject. See Attach object to another existing object for explanations. #import <objc/run...

Extension methods are useful to extend the behaviour of libraries we don't own. They are used similar to instance methods thanks to the compiler's syntactic sugar: Sub Main() Dim stringBuilder = new StringBuilder() 'Extension called directly on the object. stringBuilder.AppendIf(t...

A good use of extension method is to make the language more functional Sub Main() Dim strings = { "One", "Two", "Three" } strings.Join(Environment.NewLine).Print() End Sub <Extension> Public Function Join(strings As IEnumerable(Of String), separa...

A namespace is a URI, but to avoid verbosity, prefixes are used as a proxy. In the following example, the prefix my-prefix is bound to the namespace http://www.example.com/my-namespace by using the special attribute xmlns:my-prefix (my-prefix can be replaced with any other prefix): <?xml versio...

import pandas as pd Create a DataFrame from a dictionary, containing two columns: numbers and colors. Each key represent a column name and the value is a series of data, the content of the column: df = pd.DataFrame({'numbers': [1, 2, 3], 'colors': ['red', 'white', 'blue']}) Show contents of d...