C#. Syntax simple examples

123

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BasicLinqSyntax
{
    class Program
    {
        static void Main(string[] args)
        {
            ProductInfo[] itemsInStock = //new[] 
            {

                new ProductInfo {Name="Mac's Coffee", Description="CoffeeWithTeeth",NumberInStock=24 },
                new ProductInfo {Name="Milk Maid Milk", Description="Milk cows love",NumberInStock=100 },
                new ProductInfo {Name="Pure Silk Tofu", Description="Bland is Possible",NumberInStock=120 },
                new ProductInfo {Name="CruchyPops", Description="Cheesy, peppery goodness",NumberInStock=2 },
                new ProductInfo {Name="Rip Off Water", Description="From the Tap to Your vallet",NumberInStock=100 },
                new ProductInfo {Name="Classic Valpo Pizza", Description="Everyone loves pizza",NumberInStock=73 }

            };

            SelectEveryThing(itemsInStock);
            SelectProductNames(itemsInStock);
            SelectWhereExample(itemsInStock);
            ProectionOfNewDataType(itemsInStock);
            GetCountFromQuery(itemsInStock);
            OrderByQuery(itemsInStock);

            
            Array objs = ProectionOfNewDataTypeReturn(itemsInStock); // with return
            foreach (object o in objs) { Console.WriteLine(o); }


            DisplayDiff();
            DisplayInterSection();
            DisplayUnion();
            DisplayConcat();
            DisplayConcatDistinct();

            Console.ReadLine();

        }

        static void SelectEveryThing(ProductInfo[] products)
        {
            Console.WriteLine("select all");
            var all = from p in products select p;
            foreach (var p in all) Console.WriteLine(p);
            Console.WriteLine("   ");
        }

        static void SelectProductNames(ProductInfo[] products)
        {
            Console.WriteLine("Only product names:");
            var names = from p in products select p.Name;
            foreach (var p in names) Console.WriteLine(p);
            Console.WriteLine("   ");
        }

        static void SelectWhereExample(ProductInfo[] products)
        {
            Console.WriteLine("SelectWhereExample:");
            var subset = from p in products where p.NumberInStock > 25 && p.Name.Length > 10 select p;
            foreach (var p in subset) Console.WriteLine(p);
            Console.WriteLine("   ");
        }

        static void ProectionOfNewDataType(ProductInfo[] products)
        {

            Console.WriteLine("ProectionOfNewDataType - will create new objects:");
            var subset = from p in products select new { p.Name, p.Description };
            foreach (var p in subset) Console.WriteLine(p);
            // return subset; // << will not compile
            Console.WriteLine("   ");
        }

        static Array ProectionOfNewDataTypeReturn(ProductInfo[] products) {
            Console.WriteLine("ProectionOfNewDataTypeReturn - will create new objects:");
            var subset = from p in products select new { p.Name, p.Description };
            foreach (var p in subset) Console.WriteLine(p);

            Console.WriteLine("   ");
            return subset.ToArray(); // << will not compile

        }

        static void GetCountFromQuery(ProductInfo[] products)
        {

            int count = (from p in products select p).Count<ProductInfo>();
            Console.WriteLine("Count in query = " + count);
            Console.WriteLine("   ");

        }

        static void ReverseSubsetQuery(ProductInfo[] products)
        {

            Console.WriteLine("select all and reverse");
            var all = from p in products select p;
            foreach (var p in all.Reverse()) Console.WriteLine(p);
            Console.WriteLine("   ");

        }

        static void OrderByQuery(ProductInfo[] products)
        {

            Console.WriteLine("OrderBy Query");
            var all = from p in products orderby p.Name ascending select p;
            foreach (var p in all.Reverse()) Console.WriteLine(p);
            Console.WriteLine("   ");

        }

        static void DisplayDiff() {
            List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };
            List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

            var carDiff = (from c in myCars select c).Except(from c2 in yourCars select c2);
            Console.WriteLine("Here is what you don't have but I do:");
            foreach (var s in carDiff) Console.WriteLine(s);
        }

        static void DisplayInterSection() {
            List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };
            List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

            var carIntersect = (from c in myCars select c).Intersect(from c2 in yourCars select c2);
            Console.WriteLine("Here is what we have in intersection:");
            foreach (var s in carIntersect) Console.WriteLine(s);
        }

        static void DisplayUnion()
        {
            List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };
            List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

            var carUnion = (from c in myCars select c).Union(from c2 in yourCars select c2);
            Console.WriteLine("Here is what we have in Union:");
            foreach (var s in carUnion) Console.WriteLine(s);
        }

        static void DisplayConcat()
        {
            List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };
            List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

            var carConcat = (from c in myCars select c).Concat(from c2 in yourCars select c2);
            Console.WriteLine("Here is what we have in Concat:");
            foreach (var s in carConcat) Console.WriteLine(s);
        }


        static void DisplayConcatDistinct()
        {
            List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };
            List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

            var carConcat = (from c in myCars select c).Concat(from c2 in yourCars select c2);
            Console.WriteLine("Here is what we have in ConcatDistinct:");
            foreach (var s in carConcat.Distinct()) Console.WriteLine(s);
        }


        static void AggregateOps() {
            double[] winterTemps = { 2.0, -21.3, 8, -4, 0, 8.2 };
            Console.WriteLine("Max temp is {0}", (from t in winterTemps select t).Max());
            Console.WriteLine("Min temp is {0}", (from t in winterTemps select t).Min());
            Console.WriteLine("Average temp is {0}", (from t in winterTemps select t).Average());
            Console.WriteLine("Sum temp is {0}", (from t in winterTemps select t).Sum());
        }

    }

    class ProductInfo
    {
        public string Name { get; set; }
        public string Description { get; set; }
        public int NumberInStock { get; set; }
        public override string ToString()
        {
            return string.Format("Name={0},Description={1},Number in Stock={2}", Name, Description, NumberInStock);
        }
    }
}

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using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace BasicLinqSyntax

{

class Program

{

static void Main(string[] args)

{

ProductInfo[] itemsInStock = //new[]

{

new ProductInfo {Name="Mac's Coffee", Description="CoffeeWithTeeth",NumberInStock=24 },

new ProductInfo {Name="Milk Maid Milk", Description="Milk cows love",NumberInStock=100 },

new ProductInfo {Name="Pure Silk Tofu", Description="Bland is Possible",NumberInStock=120 },

new ProductInfo {Name="CruchyPops", Description="Cheesy, peppery goodness",NumberInStock=2 },

new ProductInfo {Name="Rip Off Water", Description="From the Tap to Your vallet",NumberInStock=100 },

new ProductInfo {Name="Classic Valpo Pizza", Description="Everyone loves pizza",NumberInStock=73 }

};

SelectEveryThing(itemsInStock);

SelectProductNames(itemsInStock);

SelectWhereExample(itemsInStock);

ProectionOfNewDataType(itemsInStock);

GetCountFromQuery(itemsInStock);

OrderByQuery(itemsInStock);

Array objs = ProectionOfNewDataTypeReturn(itemsInStock); // with return

foreach (object o in objs) { Console.WriteLine(o); }

DisplayDiff();

DisplayInterSection();

DisplayUnion();

DisplayConcat();

DisplayConcatDistinct();

Console.ReadLine();

}

static void SelectEveryThing(ProductInfo[] products)

{

Console.WriteLine("select all");

var all = from p in products select p;

foreach (var p in all) Console.WriteLine(p);

Console.WriteLine(" ");

}

static void SelectProductNames(ProductInfo[] products)

{

Console.WriteLine("Only product names:");

var names = from p in products select p.Name;

foreach (var p in names) Console.WriteLine(p);

Console.WriteLine(" ");

}

static void SelectWhereExample(ProductInfo[] products)

{

Console.WriteLine("SelectWhereExample:");

var subset = from p in products where p.NumberInStock > 25 && p.Name.Length > 10 select p;

foreach (var p in subset) Console.WriteLine(p);

Console.WriteLine(" ");

}

static void ProectionOfNewDataType(ProductInfo[] products)

{

Console.WriteLine("ProectionOfNewDataType - will create new objects:");

var subset = from p in products select new { p.Name, p.Description };

foreach (var p in subset) Console.WriteLine(p);

// return subset; // << will not compile

Console.WriteLine(" ");

}

static Array ProectionOfNewDataTypeReturn(ProductInfo[] products) {

Console.WriteLine("ProectionOfNewDataTypeReturn - will create new objects:");

var subset = from p in products select new { p.Name, p.Description };

foreach (var p in subset) Console.WriteLine(p);

Console.WriteLine(" ");

return subset.ToArray(); // << will not compile

}

static void GetCountFromQuery(ProductInfo[] products)

{

int count = (from p in products select p).Count<ProductInfo>();

Console.WriteLine("Count in query = " + count);

Console.WriteLine(" ");

}

static void ReverseSubsetQuery(ProductInfo[] products)

{

Console.WriteLine("select all and reverse");

var all = from p in products select p;

foreach (var p in all.Reverse()) Console.WriteLine(p);

Console.WriteLine(" ");

}

static void OrderByQuery(ProductInfo[] products)

{

Console.WriteLine("OrderBy Query");

var all = from p in products orderby p.Name ascending select p;

foreach (var p in all.Reverse()) Console.WriteLine(p);

Console.WriteLine(" ");

}

static void DisplayDiff() {

List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };

List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

var carDiff = (from c in myCars select c).Except(from c2 in yourCars select c2);

Console.WriteLine("Here is what you don't have but I do:");

foreach (var s in carDiff) Console.WriteLine(s);

}

static void DisplayInterSection() {

List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };

List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

var carIntersect = (from c in myCars select c).Intersect(from c2 in yourCars select c2);

Console.WriteLine("Here is what we have in intersection:");

foreach (var s in carIntersect) Console.WriteLine(s);

}

static void DisplayUnion()

{

List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };

List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

var carUnion = (from c in myCars select c).Union(from c2 in yourCars select c2);

Console.WriteLine("Here is what we have in Union:");

foreach (var s in carUnion) Console.WriteLine(s);

}

static void DisplayConcat()

{

List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };

List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

var carConcat = (from c in myCars select c).Concat(from c2 in yourCars select c2);

Console.WriteLine("Here is what we have in Concat:");

foreach (var s in carConcat) Console.WriteLine(s);

}

static void DisplayConcatDistinct()

{

List<string> myCars = new List<string>() { "Yugo", "Aztec", "BMW" };

List<string> yourCars = new List<string>() { "BMW", "SAAB", "Aztec" };

var carConcat = (from c in myCars select c).Concat(from c2 in yourCars select c2);

Console.WriteLine("Here is what we have in ConcatDistinct:");

foreach (var s in carConcat.Distinct()) Console.WriteLine(s);

}

static void AggregateOps() {

double[] winterTemps = { 2.0, -21.3, 8, -4, 0, 8.2 };

Console.WriteLine("Max temp is {0}", (from t in winterTemps select t).Max());

Console.WriteLine("Min temp is {0}", (from t in winterTemps select t).Min());

Console.WriteLine("Average temp is {0}", (from t in winterTemps select t).Average());

Console.WriteLine("Sum temp is {0}", (from t in winterTemps select t).Sum());

}

class ProductInfo

{

public string Name { get; set; }

public string Description { get; set; }

public int NumberInStock { get; set; }

public override string ToString()

{

return string.Format("Name={0},Description={1},Number in Stock={2}", Name, Description, NumberInStock);

}

C#. Syntax simple examples

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