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ConnectionMultiplexer conn = /* initialization */; var profiler = new ToyProfiler(); conn.RegisterProfiler(profiler); var threads = new List<Thread>(); var perThreadTimings = new ConcurrentDictionary<Thread, List<IProfiledCommand>>(); for (var i = 0; i < 16; i++) {...

public class IHtmlStringTypeHandler : SqlMapper.TypeHandler<IHtmlString> { public override void SetValue( IDbDataParameter parameter, IHtmlString value) { parameter.DbType = DbType.String; parameter.Value = value?.ToHtmlString(); } pu...

A common scenario in database queries is IN (...) where the list here is generated at runtime. Most RDBMS lack a good metaphor for this - and there is no universal cross-RDBMS solution for this. Instead, dapper provides some gentle automatic command expansion. All that is requires is a supplied para...

Sometimes, you want to do the same thing multiple times. Dapper supports this on the Execute method if the outermost parameter (which is usually a single anonymous type, or a domain model instance) is actually provided as an IEnumerable sequence. For example: Order[] orders = ... // update the tot...

Open Visual Studio In the toolbar, go to File → New Project Select the Console Application project type Open the file Program.cs in the Solution Explorer Add the following code to Main(): public class Program { public static void Main() { // Prints a message to the conso...

Extension methods were introduced in C# 3.0. Extension methods extend and add behavior to existing types without creating a new derived type, recompiling, or otherwise modifying the original type. They are especially helpful when you cannot modify the source of a type you are looking to enhance. Ex...

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, ...

Initialize a collection type with values: var stringList = new List<string> { "foo", "bar", }; Collection initializers are syntactic sugar for Add() calls. Above code is equivalent to: var temp = new List<string>(); temp.Add("foo"); temp.A...

Equals Checks whether the supplied operands (arguments) are equal "a" == "b" // Returns false. "a" == "a" // Returns true. 1 == 0 // Returns false. 1 == 1 // Returns true. false == true // Returns false. false == false // Return...

Full expressions can also be used in interpolated strings. var StrWithMathExpression = $"1 + 2 = {1 + 2}"; // -> "1 + 2 = 3" string world = "world"; var StrWithFunctionCall = $"Hello, {world.ToUpper()}!"; // -> "Hello, WORLD!" Live Demo...

Expression-bodied function members allow the use of lambda expressions as member bodies. For simple members, it can result in cleaner and more readable code. Expression-bodied functions can be used for properties, indexers, methods, and operators. Properties public decimal TotalPrice => Base...

Exception filters give developers the ability to add a condition (in the form of a boolean expression) to a catch block, allowing the catch to execute only if the condition evaluates to true. Exception filters allow the propagation of debug information in the original exception, where as using an...

String interpolation allows the developer to combine variables and text to form a string. Basic Example Two int variables are created: foo and bar. int foo = 34; int bar = 42; string resultString = $"The foo is {foo}, and the bar is {bar}."; Console.WriteLine(resultString); ...

The ?. operator and ?[...] operator are called the null-conditional operator. It is also sometimes referred to by other names such as the safe navigation operator. This is useful, because if the . (member accessor) operator is applied to an expression that evaluates to null, the program will throw ...

When a type is defined without a constructor: public class Animal { } then the compiler generates a default constructor equivalent to the following: public class Animal { public Animal() {} } The definition of any constructor for the type will suppress the default constructor genera...

public class Animal { public string Name { get; set; } public Animal() : this("Dog") { } public Animal(string name) { Name = name; } } var dog = new Animal(); // dog.Name will be set to "Dog" by default. var cat = new Ani...

A static constructor is called the first time any member of a type is initialized, a static class member is called or a static method. The static constructor is thread safe. A static constructor is commonly used to: Initialize static state, that is state which is shared across different instan...

A constructor of a base class is called before a constructor of a derived class is executed. For example, if Mammal extends Animal, then the code contained in the constructor of Animal is called first when creating an instance of a Mammal. If a derived class doesn't explicitly specify which constru...

When an object graph is finalized, the order is the reverse of the construction. E.g. the super-type is finalized before the base-type as the following code demonstrates: class TheBaseClass { ~TheBaseClass() { Console.WriteLine("Base class finalized!"); } } ...

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())) { ...