Tutorial by Examples: sin

using System.Data; using System.Linq; using Dapper; class Program { static void Main() { using (IDbConnection db = new SqlConnection("Server=myServer;Trusted_Connection=true")) { db.Open(); var result = db.Query<string>(&quo...

LINQPad is great for testing database queries and includes NuGet integration. To use Dapper in LINQPad press F4 to open the Query Properties and then select Add NuGet. Search for dapper dot net and select Add To Query. You will also want to click Add namespaces and highlight Dapper to include the Ex...

string fullOrRelativePath = "testfile.txt"; string fileData; using (var reader = new StreamReader(fullOrRelativePath)) { fileData = reader.ReadToEnd(); } Note that this StreamReader constructor overload does some auto encoding detection, which may or may not conform to the ...

Extension methods can also be used like ordinary static class methods. This way of calling an extension method is more verbose, but is necessary in some cases. static class StringExtensions { public static string Shorten(this string text, int length) { return text.Substring(0, ...

var date = new DateTime(2015, 11, 11); var str = $"It's {date:MMMM d, yyyy}, make a wish!"; System.Console.WriteLine(str); You can also use the DateTime.ToString method to format the DateTime object. This will produce the same output as the code above. var date = new DateTime(2015, 1...

string requestUri = "http://www.example.com"; string responseData; HttpWebRequest request = (HttpWebRequest)WebRequest.Create(parameters.Uri); WebResponse response = request.GetResponse(); using (StreamReader responseReader = new StreamReader(response.GetResponseStream())) { ...

string requestUri = "http://www.example.com"; string responseData; using (var client = new WebClient()) { responseData = client.DownloadString(requestUri); }

HttpClient is available through NuGet: Microsoft HTTP Client Libraries. string requestUri = "http://www.example.com"; string responseData; using (var client = new HttpClient()) { using(var response = client.GetAsync(requestUri).Result) { response.EnsureSuccessStatus...

string requestUri = "http://www.example.com"; string requestBodyString = "Request body string."; string contentType = "text/plain"; string requestMethod = "POST"; HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUri) { Method = reque...

string requestUri = "http://www.example.com"; string requestBodyString = "Request body string."; string contentType = "text/plain"; string requestMethod = "POST"; byte[] responseBody; byte[] requestBodyBytes = Encoding.UTF8.GetBytes(requestBodyS...

HttpClient is available through NuGet: Microsoft HTTP Client Libraries. string requestUri = "http://www.example.com"; string requestBodyString = "Request body string."; string contentType = "text/plain"; string requestMethod = "POST"; var request = new ...

The finally { ... } block of a try-finally or try-catch-finally will always execute, regardless of whether an exception occurred or not (except when a StackOverflowException has been thrown or call has been made to Environment.FailFast()). It can be utilized to free or clean up resources acquired i...

var oneNumber = new[] {5}; var theOnlyNumber = oneNumber.Single(); Console.WriteLine(theOnlyNumber); //5 var numbers = new[] {1,2,3,4,5}; var theOnlyNumberSmallerThanTwo = numbers.Single(n => n < 2); Console.WriteLine(theOnlyNumberSmallerThanTwo); //1 The following throws Invalid...

var oneNumber = new[] {5}; var theOnlyNumber = oneNumber.SingleOrDefault(); Console.WriteLine(theOnlyNumber); //5 var numbers = new[] {1,2,3,4,5}; var theOnlyNumberSmallerThanTwo = numbers.SingleOrDefault(n => n < 2); Console.WriteLine(theOnlyNumberSmallerThanTwo); //1 var theOnl...

using is syntactic sugar that allows you to guarantee that a resource is cleaned up without needing an explicit try-finally block. This means your code will be much cleaner, and you won't leak non-managed resources. Standard Dispose cleanup pattern, for objects that implement the IDisposable interf...

The using static [Namespace.Type] directive allows the importing of static members of types and enumeration values. Extension methods are imported as extension methods (from just one type), not into top-level scope. 6.0 using static System.Console; using static System.ConsoleColor; using static ...

To make a class support collection initializers, it must implement IEnumerable interface and have at least one Add method. Since C# 6, any collection implementing IEnumerable can be extended with custom Add methods using extension methods. class Program { static void Main() { va...

Apostrophes char apostrophe = '\''; Backslash char oneBackslash = '\\';

Backslash // The filename will be c:\myfile.txt in both cases string filename = "c:\\myfile.txt"; string filename = @"c:\myfile.txt"; The second example uses a verbatim string literal, which doesn't treat the backslash as an escape character. Quotes string text = "\&...

You are allowed to create and throw exceptions in your own code. Instantiating an exception is done the same way that any other C# object. Exception ex = new Exception(); // constructor with an overload that takes a message string Exception ex = new Exception("Error message"); Yo...