c# async anonymous functions

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/statements-expressions-operators/lambda-expressions

(input parameters) => expression

(input parameters) => {statments}

c# azure CloudStorageAccount

https://docs.microsoft.com/en-us/dotnet/api/microsoft.azure.storage.cloudstorageaccount?view=azure-dotnet

c# how to create document for our user written class

  ///

        /// Gets or sets an optional SAS url for accessing a test queue
        ///

xml tags for user written class documentation
summary tag, param tag

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/xmldoc/recommended-tags-for-documentation-comments#:~:text=The%20C%23%20compiler%20processes%20documentation,such%20as%20DocFX%20or%20Sandcastle.

c# how create object with parameters , construciton intialization

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/how-to-initialize-objects-by-using-an-object-initializer

call default constructor, set parameters with values

// Make the same declaration by using an object initializer and sending // arguments for the first and last names. The default constructor is // invoked in processing this declaration, not the constructor that has // two parameters. StudentName student2 = new StudentName { FirstName = "Craig", LastName = "Playstead" };

c# TimeSpan?

https://docs.microsoft.com/en-us/dotnet/api/system.timespan?view=netcore-3.1

calculate difference between datetime

// Define two dates.

DateTime date1 = new DateTime(2010, 1, 1, 8, 0, 15);

DateTime date2 = new DateTime(2010, 8, 18, 13, 30, 30);

// Calculate the interval between the two dates.

TimeSpan interval = date2 - date1;

Console.WriteLine("{0} - {1} = {2}", date2, date1, interval.ToString());

// Display individual properties of the resulting TimeSpan object.

Console.WriteLine(" {0,-35} {1,20}", "Value of Days Component:", interval.Days);

Console.WriteLine(" {0,-35} {1,20}", "Total Number of Days:", interval.TotalDays);

Console.WriteLine(" {0,-35} {1,20}", "Value of Hours Component:", interval.Hours);

Console.WriteLine(" {0,-35} {1,20}", "Total Number of Hours:", interval.TotalHours);

Console.WriteLine(" {0,-35} {1,20}", "Value of Minutes Component:", interval.Minutes);

Console.WriteLine(" {0,-35} {1,20}", "Total Number of Minutes:", interval.TotalMinutes);

Console.WriteLine(" {0,-35} {1,20:N0}", "Value of Seconds Component:", interval.Seconds);

Console.WriteLine(" {0,-35} {1,20:N0}", "Total Number of Seconds:", interval.TotalSeconds);

Console.WriteLine(" {0,-35} {1,20:N0}", "Value of Milliseconds Component:", interval.Milliseconds);

Console.WriteLine(" {0,-35} {1,20:N0}", "Total Number of Milliseconds:", interval.TotalMilliseconds);

Console.WriteLine(" {0,-35} {1,20:N0}", "Ticks:", interval.Ticks);

// This example displays the following output:

// 8/18/2010 1:30:30 PM - 1/1/2010 8:00:15 AM = 229.05:30:15

// Value of Days Component: 229

// Total Number of Days: 229.229340277778

// Value of Hours Component: 5

// Total Number of Hours: 5501.50416666667

// Value of Minutes Component: 30

// Total Number of Minutes: 330090.25

// Value of Seconds Component: 15

// Total Number of Seconds: 19,805,415

// Value of Milliseconds Component: 0

// Total Number of Milliseconds: 19,805,415,000

// Ticks: 198,054,150,000,000

c# extension method

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/extension-methods

extend exist class, using extension method
extension method
1)static method
1) using extension method using directive

c# ReadDocumentAsync?

ReadDocumentAsync(String, RequestOptions, CancellationToken)
Reads a Document from the Azure Cosmos DB service as an asynchronous ope

c# what using?

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using-statement
wrapes try, finally with using statement, call the disposable method

code snippet

string manyLines=@"This is line one
This is line two
Here is line three
The penultimate line is line four
This is the final, fifth line.";

using var reader = new StringReader(manyLines);
string? item;
do {
    item = reader.ReadLine();
    Console.WriteLine(item);
} while(item != null);

c# what is nameof

nameof
will return name of the variable, type(class, interface..), fucntion/method name

reference:

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/nameof

code snippet:

Console.WriteLine(nameof(System.Collections.Generic)); // output: Generic

Console.WriteLine(nameof(Listtring

>)); // output: List

Console.WriteLine(nameof(List<string>.Count)); // output: Count

Console.WriteLine(nameof(List<string>.Add)); // output: Add

var numbers = new List<string> { "ab", "cd", "ef" };

Console.WriteLine(nameof(numbers)); // output: numbers

Console.WriteLine(nameof(numbers.Count)); // output: Count

Console.WriteLine(nameof(numbers.Add)); // output: Add

c# what is ??

The null-coalescing operator ?? returns the value of its left-hand operand if it isn't null; otherwise, it evaluates the right-hand operand and returns its result. The ?? operator doesn't evaluate its right-hand operand if the left-hand operand evaluates to non-null.

refernce: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/null-coalescing-operator