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 ...
Code can and should throw exceptions in exceptional circumstances. Examples of this include:
Attempting to read past the end of a stream
Not having necessary permissions to access a file
Attempting to perform an invalid operation, such as dividing by zero
A timeout occurring when downloading a...
var persons = new[]
{
new {Id = 1, Name = "Foo"},
new {Id = 2, Name = "Bar"},
new {Id = 3, Name = "Fizz"},
new {Id = 4, Name = "Buzz"}
};
var names = persons.Select(p => p.Name);
Console.WriteLine(string.Join(",", names....
This method returns an IEnumerable with all the elements that meets the lambda expression
Example
var personNames = new[]
{
"Foo", "Bar", "Fizz", "Buzz"
};
var namesStartingWithF = personNames.Where(p => p.StartsWith("F"));
Console.W...
var numbers1to5 = new[] {1, 2, 3, 4, 5};
var numbers4to8 = new[] {4, 5, 6, 7, 8};
var numbers1to8 = numbers1to5.Concat(numbers4to8);
Console.WriteLine(string.Join(",", numbers1to8));
//1,2,3,4,5,4,5,6,7,8
Note that duplicates are kept in the result. If this is undesirable, use...
var numbers = new[] {1,2,3,4,5};
var firstNumber = numbers.First();
Console.WriteLine(firstNumber); //1
var firstEvenNumber = numbers.First(n => (n & 1) == 0);
Console.WriteLine(firstEvenNumber); //2
The following throws InvalidOperationException with message "Sequence contain...
var numbers = new[] {1,2,3,4,5};
var lastNumber = numbers.Last();
Console.WriteLine(lastNumber); //5
var lastEvenNumber = numbers.Last(n => (n & 1) == 0);
Console.WriteLine(lastEvenNumber); //4
The following throws InvalidOperationException:
var lastNegativeNumber = numbers.Last(n...
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...
For classes, interfaces, delegate, array, nullable (such as int?) and pointer types, default(TheType) returns null:
class MyClass {}
Debug.Assert(default(MyClass) == null);
Debug.Assert(default(string) == null);
For structs and enums, default(TheType) returns the same as new TheType():
struct...
Enumerable.Select returns an output element for every input element.
Whereas Enumerable.SelectMany produces a variable number of output elements for each input element. This means that the output sequence may contain more or fewer elements than were in the input sequence.
Lambda expressions passe...
This method takes the first n elements from an enumerable.
var numbers = new[] {1,2,3,4,5};
var threeFirstNumbers = numbers.Take(3);
Console.WriteLine(string.Join(",", threeFirstNumbers.ToArray()));
//1,2,3
var mixed = new object[] {1,"Foo",2,"Bar",3,"Fizz",4,"Buzz"};
var numbers = mixed.OfType<int>();
Console.WriteLine(string.Join(",", numbers.ToArray()));
//1,2,3,4
Returns a new dictionary from the source IEnumerable using the provided keySelector function to determine keys. Will throw an ArgumentException if keySelector is not injective(returns a unique value for each member of the source collection.) There are overloads which allow one to specify the value t...
