private AA.AsinJsonFile findSeriesFileDirectOrSku(Book.Part part, bool fileOnly, string filePrefix, GetProductsDelegate getProducts)
{
// try to find sims by series file, either locally, relative or absolute
// precondition content meta file is available
// either by ASIN (single-part book) or by SKU (multipart book)
// get asin
var afi = part.AaxFileItem;
string asin = afi.ContentMetadataFile?.ASIN;
if (asin is null)
{
Log(3, this, () => $"ASIN not found.");
return(null);
}
Log(3, this, () => $"ASIN={asin}{(filePrefix.IsNullOrWhiteSpace() ? string.Empty : $", prefix={filePrefix}")}");
static async Task Main(string[] args)
{
Console.WriteLine("------------------Mutable------------------------");
//Values are mutable
int x = 10;
x = 20;
x = 30;
x = 50;
Console.WriteLine(x);
Console.WriteLine("------------------Dynamically implemented properties------------------------");
Students student = new Students("James", 18, "21/ug-223/BSCS", 3000);
//age mutable
student.age = 28;
//name is readyOnly(immutable); cannot rewrite
//student.name="Job";
//regNo is mutable
student.regNo = "21/ug-335/BSSE-S";
student.tution = 7000;
Console.WriteLine(student.name);
Console.WriteLine(student.age);
Console.WriteLine(student.regNo);
Console.WriteLine(student.tution);
Console.WriteLine("------------------Implicity typing------------------------");
var scores = new[] { 1, 2.5, 3, 4, 5 };
foreach (double element in scores)
{
Console.WriteLine(element);
}
Console.WriteLine("------------------Object and collactions initializers------------------------");
Products phone = new Products {
pPrice = 3000, pName = "Smart Phone", pQuantity = 20, pBrand = "Oppo"
};
phone = new Products();
Console.WriteLine(phone.pName + "" + phone.pPrice);
// List<Products> products = new List<Products>{
// new Products { pPrice = 3000, pName = "Smart Phone", pQuantity = 20, pBrand = "Oppo" },
// new Products { pPrice = 6000, pName = "Smart Tv", pQuantity = 10, pBrand = "Samsung" } ,
// new Products { pPrice = 4000, pName = "Fridge", pQuantity = 5, pBrand = "LG" },
// new Products { pPrice = 5000, pName = "Oven", pQuantity = 2, pBrand = "LG" },
// };
GetProductsDelegate productsDelegate = new GetProductsDelegate(getProducts);
List <Products> products = productsDelegate.Invoke();
Console.WriteLine("------------------Lambda expression ------------------------");
//Lambda expression
//Lambda calculus
//Anything coming after the arrow funtion, should be condition.
List <Products> hightPrices = products.FindAll(value => value.pPrice < 4000);
foreach (Products product in hightPrices)
{
Console.WriteLine(product.pName + " " + product.pPrice);
}
Console.WriteLine("------------------LINQ Expression queries------------------------");
//
IEnumerable <Products> lowPrices =
from product in products where product.pPrice < 5000 orderby product.pName ascending select product;
foreach (Products product in lowPrices)
{
Console.WriteLine(product.pName + " " + product.pPrice);
}
Console.WriteLine("------------------ANONYMOUS DATATYPE------------------------");
// Example in Js
/*
* Example in Js
* var user={
* fristname:'',
* lastname:'',
* nationality:'',
* }
*/
// Example in C#
var user = new
{
firstname = "Victor",
lastname = "Manakana",
nationality = "SA"
};
Console.WriteLine(user.firstname);
Console.WriteLine(user.lastname);
Console.WriteLine(user.nationality);
//Dynamic
Console.WriteLine("--------------------------dynamic typing ----------------------------");
Calculator <double> calculator = new Calculator <double>();
dynamic sum = calculator.sum(10.9, 12.9);
Console.WriteLine("Sum is" + sum);
//Optional parameters
Console.WriteLine("--------------------------Optional parameters ----------------------------");
Lecturers lecturers = new Lecturers(200.0);
Console.WriteLine("Sum is: " + lecturers.name + " " + lecturers.wages);
Lecturers lecturers2 = new Lecturers(name: "James", wages: 200.0);
//Asynchronous
Console.WriteLine("--------------------------Asynchronous----------------------------");
// synchronization , asynchronization
// T1 & T2, waits for t1 to finish
// OS dictionary
Program program = new Program();
await program.checkin();
await fetchUserData();
await fetchResultsData();
//Asynchronous Pending tasks
Console.WriteLine("--------------------------Moving next within Pending tasks----------------------------");
IAsyncEnumerator <int> asyncEnumerator = pendingTasks(1, 4).GetAsyncEnumerator();
while (await asyncEnumerator.MoveNextAsync())
{
Console.WriteLine($"Current task value is :{asyncEnumerator.Current}");
}
//Tasks, threads, Jobs
Console.WriteLine("--------------------------Custom task types revisited----------------------------");
// Thread thread= new Thread(new ThreadStart(thread1));
// thread.Start();
// await doPurchaseJob1();
//Run multiple tasks at the same time
//Tasks, threads, Jobs
Console.WriteLine("--------------------------Run multiple tasks at the same time----------------------------");
List <Task> tasks = new List <Task>();
tasks.Add(Task.Run(async() => {
await Task.Delay(1000);
Console.WriteLine("Task1");
}));
tasks.Add(Task.Run(async() => {
await Task.Delay(2000);
Console.WriteLine("Task2");
}));
tasks.Add(Task.Run(async() => {
//await Task.Delay(3000);
await fetchUserData();
Console.WriteLine("Task3");
}));
tasks.Add(Task.Run(async() => {
await Task.Delay(2000);
Console.WriteLine("Task4");
}));
// Task.WaitAll(tasks.ToArray());
//Convariance and contravariance
Console.WriteLine("-------------------------------------Convariance and contravariance------------------------------");
//------------contravariance
// Cow cow= new Mammars();
Mammars mammars = new Cow();
// Mammars mammars1= new Animal();
Animal animal = new Mammars();
//------------convariance
IEnumerable <Animal> animals = new List <Mammars>();
//out , in
//SmartPhone<PhoneTypes> smartPhones= new List<IApple>();
Console.WriteLine("-------------------------------------Convariance and contravariance------------------------------");
string studentDetails = String.Format(" Hey Mr {0} and {1}", "James", "John");
long workerId = 11100000;
string workerDetails = String.Format(" Hey My ID is {0}", workerId);
// Decimal
//double x= 30.00000000000000000000000000000000E25;
Decimal wages = 5000000000000000.50m;
//5,000,000,000,000,000
string engineerWages = String.Format("James wages is {0:N0}", wages);
Console.WriteLine(studentDetails);
Console.WriteLine(wages);
String[] students = { "Victor", "Faith", "Khoza" };
Decimal[] marks = new Decimal[] { 80000000, 8000000, 90000000 };
String[] positions = new String[] { "Senior softwareEng ", "Senior softwareEng", "Senior softwareEng" };
var stringBuilder = new System.Text.StringBuilder();
stringBuilder.Append(String.Format("{0,5} {1,8} {2,7} \n\n", "Engineers", "Salary", "Position"));
for (int i = 0; i < students.Length; i++)
{
stringBuilder.Append(String.Format("{0,5} {1,8:N0} {2,7} \n\n", students[i], marks[i], positions[i]));
}
Console.WriteLine(stringBuilder);
}
private bool findSeriesFile(Book.Part part, bool fileOnly, string filePrefix, GetProductsDelegate getProducts)
{
try {
var simsBySeriesFile = findSeriesFileDirectOrSku(part, fileOnly, filePrefix, getProducts);
if (simsBySeriesFile is null || simsBySeriesFile.Filename is null)
{
part.AaxFileItem.SimsBySeriesFile = new AA.AsinJsonFile(null, null);
return(false);
}
part.AaxFileItem.SimsBySeriesFile = simsBySeriesFile;
string metafile = simsBySeriesFile.Filename;
Log(3, this, () => $"\"{metafile.SubstitUser ()}\"");
return(true);
} catch (Exception exc) {
Log(1, this, () => exc.ToShortString());
return(false);
}
}
