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Use the Skip() method in C# to skip number of elements in an array.Let’s say the following is our array −int[] arr = { 10, 20, 30, 40, 50 };To skip the first two elements, use the Skip() method and add argument as 2 −arr.Skip(2);Let us see an example −Example Live Demousing System.IO; using System; using System.Linq; public class Demo { public static void Main() { int[] arr = { 10, 20, 30, 40, 50 }; Console.WriteLine("Initial Array..."); foreach (var res in arr) { Console.WriteLine(res); ... Read More
Set a list −List myList = new List() { 5, 10, 17, 19, 23, 33 };Let us say you need to find an element that is divisible by 2. For that, use the Find() method −int val = myList.Find(item => item % 2 == 0);Here is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Demo { static void Main() { List myList = new List() { 5, 10, 17, 19, 23, 33 }; Console.WriteLine("List: "); foreach(int i in myList) { Console.WriteLine(i); } int val = myList.Find(item => item % 2 == 0); Console.WriteLine("Element that divides by zero: "+val); } }OutputList: 5 10 17 19 23 33 Element that divides by zero: 10
We have two types of MYSQL generated columns as follows −VIRTUAL GENERATED COLUMNAs the name suggests, this kind of generated column will not take any disk space. It can be generated with or without using the keyword ‘virtual’. To understand we are illustrating it in the following example −Examplemysql> Create table triangle(SideA DOUBLE, SideB DOUBLE, SideC DOUBLE AS (SQRT(SideA * SideB + SideB * SideB))); Query OK, 0 rows affected (0.44 sec) mysql> Describe Triangle; +-------+--------+------+-----+---------+-------------------+ | Field | Type | Null | Key | Default | Extra | +-------+--------+------+-----+---------+-------------------+ | SideA ... Read More
The ToDictionary method is an extension method in C# and converts a collection into Dictionary.Firstly, create a string array −string[] str = new string[] {"Car", "Bus", "Bicycle"};Now, use the Dictionary method to convert a collection to Dictionary −str.ToDictionary(item => item, item => true);Here is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Demo { static void Main() { string[] str = new string[] {"Car", "Bus", "Bicycle"}; // key and value under ToDictionary var d = str.ToDictionary(item => item, item => true); foreach (var ele ... Read More
Use the Sort method to sort the KeyValuePairs collection.Firstly, set the collection −var myList = new List(); // adding elements myList.Add(new KeyValuePair(1, 20)); myList.Add(new KeyValuePair(2, 15)); myList.Add(new KeyValuePair(3, 35)); myList.Add(new KeyValuePair(4, 50)); myList.Add(new KeyValuePair(5, 25));To sort, use the Sort() method. With that, we have used the CompareTo() method to compare values −myList.Sort((x, y) => (y.Value.CompareTo(x.Value)));The following is the complete code −Example Live Demousing System; using System.Collections.Generic; class Program { static void Main() { var myList = new List(); // adding elements myList.Add(new KeyValuePair(1, 20)); myList.Add(new KeyValuePair(2, 15)); ... Read More
For adding MySQL virtual GENERATED COLUMNS in a table, we can use the same syntax as adding a column just adding “AS(expression)” after the data type. Its syntax would be as follows −SyntaxALTER TABLE table_name ADD COLUMN column_name AS(expression);Examplemysql> ALTER TABLE employee_data ADD COLUMN FULLName Varchar(200) AS(CONCAT_WS(" ", 'First_name', 'Last_name')); Query OK, 0 rows affected (0.49 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> Describe employee_data; +------------+--------------+------+-----+---------+-------------------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+-------------------+ | ID ... Read More
The KeyNotFoundException is thrown when a key you are finding is not available in the Dictionary collection.Let us see an example −Example Live Demousing System; using System.Collections.Generic; public class Demo { public static void Main() { try { var dict = new Dictionary() { {"TV", "Electronics"}, {"Laptop", "Computers"}, }; Console.WriteLine(dict["Pen Drive"]); } catch (Exception e) { Console.WriteLine(e); } } ... Read More
Followings are some basic differences between MySQL stored GENERATED COLUMNS and MySQL virtual GENERATED COLUMNS −In terms of Disk SpaceIf we see the difference in terms of disk space then virtual generated columns would not take any disk space. On the other hand, the stored generated column would take disk space.In terms of operationIf we see the difference in terms of operation then virtual generated columns are INPLACE operations which means that the table definition is changed without having to recopy all the data again. On the other hand, stored generated columns are a copy operation and it has the ... Read More
Use the orderby leyword to sort a list in ascending or descending order.The following is the list −List myList = new List(); myList.Add("truck"); myList.Add("bus"); myList.Add("bicycle"); myList.Add("motorbike");Now let us sort the list in descending order −myLen = from element in myList orderby element.Length descending select element;Here is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Demo { static void Main() { List myList = new List(); myList.Add("truck"); myList.Add("bus"); myList.Add("bicycle"); myList.Add("motorbike"); var myLen = from element in myList ... Read More
The interface between a process and an operating system is provided by system calls. In general, system calls are available as assembly language instructions. They are also included in the manuals used by the assembly level programmers. System calls are usually made when a process in user mode requires access to a resource. Then it requests the kernel to provide the resource via a system calls.In general, system calls are required in the following situations −If a file system requires the creation or deletion of files. Reading and writing from files also require a system call.Creation and management of new ... Read More