// Configure open file dialog box Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog(); dlg.Title = “Select File”; // dialog title dlg.FileName = “”; // Default file name dlg.DefaultExt = “.csv”; // Default file extension dlg.Filter = “CSV File (.csv)|*.csv|All Files (*.*)|*.*”; // Filter files by extension // Show the dialog and process result if (dlg.ShowDialog() == true) […]

A very simple method for writing to a file, not forget to include using System.IO;. string filename = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) + @”\test.txt”; string content = “This is the new file content”; File.WriteAllText(filename, content);

The setName funcion demostrates simple data validation on the argument value. void setName(string value) { // validate empty if (string.IsNullOrWhiteSpace(value)) { throw new ArgumentNullException(“Please enter a value”); } // validate length if (value.Length > 10) { throw new ArgumentException(“The value is too long”); } // value is valid MessageBox.Show(“The value is valid”); } When calling […]

A var type can be checked using the ‘is’ statement var a = 1.0; if (a is int) { MessageBox.Show(“int”); } else { MessageBox.Show(“is NOT int”); }

The code below shows the short hand and long hand syntax for defining class properties. public class Example { // class property short hand public string Firstname {get; set;} // class property long hand private string _Lastname; public string Lastame { get {return _Lastname} set {_Lastname = value} } }

The LINQ example below creates a generic collection of the class Car. Then using a LINQ statement the collection is filtered to find cars that are newer than 2009. List myCars = new List() { new Car() { Make=”BMW”, Model=”550i”, Year=2009 }, new Car() { Make=”Toyota”, Model=”4Runner”, Year=2010 }, new Car() { Make=”BMW”, Model=”745li”, Year=2008 […]

Here is an example of using enum with a tryParse. The program asks the user to enter a new state. The tryParse then attempts to convert the input into a enum. // define current state MyState currentState = MyState.off; // get value from user Console.WriteLine(“Please enter the new state”); string input = Console.ReadLine(); if (Enum.TryParse(input, […]

Add seven days to the current time. DateTime start = DateTime.Now; Console.WriteLine(“Start date = ” + start.ToString(“dd/MM/yyyy hh:mm:ss”)); DateTime end = start.AddDays(7); Console.WriteLine(“End date = ” + end.ToString(“dd/MM/yyyy hh:mm:ss”)); Other methods for defining a DateTime object DateTime start = DateTime.Parse(“23/01/1984 01:02:03”); DateTime start = new DateTime(1984, 01, 23, 01, 02, 03);