 using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Xml;
using System.IO;

//DBConnection
class DBConnection
{
  public static SqlConnection GetConnection()
  {
    String xmlString = System.IO.File.ReadAllText("mssql.xml");
    string username;
    string password;
    string schema;
    string host;
    using (XmlReader reader = XmlReader.Create(new StringReader(xmlString)))
    {
      reader.ReadToFollowing("username");
      username = reader.ReadElementContentAsString();
      reader.ReadToFollowing("password");
      password = reader.ReadElementContentAsString();
      reader.ReadToFollowing("host");
      host = reader.ReadElementContentAsString();
      reader.ReadToFollowing("schema");
      schema = reader.ReadElementContentAsString();
    }
    string connection_string = "Data Source=" + host + ";Initial Catalog=" + schema + ";User id=" + username + ";Password=" + password + ";";
    SqlConnection conn = new SqlConnection(connection_string);
    return conn;
  }
}

//DAO SqlConnection SqlCommand SqlDataReader while (reader.Read()){}

//Insert User
string query = $"Insert into person (name, username, password, contactNo) Values ('{user.Name}', '{user.UserName}', '{user.Password}', '{user.ContactNo}');";
SqlConnection con = DBConnection.GetConnection();
SqlCommand command = new SqlCommand(query, con);
try
{
  con.Open();
  command.ExecuteNonQuery();
  return 4;
}

//Get id
string query = $"Select id from owner where name = '{owner_name}';";
SqlConnection conn = DBConnection.GetConnection();
SqlCommand cmd = new SqlCommand(query, conn);
try
{
  conn.Open();
  SqlDataReader reader = cmd.ExecuteReader();
  while (reader.Read())
  {
    return reader.GetInt32(0);
  }
}

//UpdateStartAndEndDate
SqlConnection con = DBConnection.GetConnection();
string query = $"Update Event Set start_date='{startDate}', end_date='{endDate}' Where id={id};";
string query2 = $"Select COUNT(*) from Event Where id={id};";
try
{
  SqlCommand cmd = new SqlCommand(query, con);   
  SqlCommand cmd2 = new SqlCommand(query2, con);   
  con.Open();
  if((Int32)(cmd2.ExecuteScalar()) == 0)
  {
    return false;
  }
  cmd.ExecuteNonQuery();
  return true;
}

//DeletePerson
string query = $"Delete from person Where name='{username}';";
string query2 = $"Select Count(*) from person Where name='{username}';";
try
{
  con.Open();
  SqlCommand cmd = new SqlCommand(query, con);
  SqlCommand cmd2 = new SqlCommand(query2, con);
  if((Int32)cmd2.ExecuteScalar() == 0)
  {
    return false;
  }
  cmd.ExecuteNonQuery();
  return true;
}

created 2 years ago by Ankit Paul

C Sharp Online Compiler

Write, Run & Share C# code online using OneCompiler's C# online compiler for free. It's one of the robust, feature-rich online compilers for C# language, running on the latest version 8.0. Getting started with the OneCompiler's C# compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C# and start coding.

Read inputs from stdin

OneCompiler's C# online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

using System;
 
namespace Sample
{
  class Test
    {
      public static void Main(string[] args)
       {
         string name;
         name = Console.ReadLine();
         Console.WriteLine("Hello {0} ", name);
	}
     }
}

About C Sharp

C# is a general purpose object-oriented programming language by Microsoft. Though initially it was developed as part of .net but later it was approved by ECMA and ISO standards.

You can use C# to create variety of applications, like web, windows, mobile, console applications and much more using Visual studio.

Syntax help

Data types

Data Type	Description	Range	size
int	To store integers	-2,147,483,648 to 2,147,483,647	4 bytes
double	to store large floating point numbers with decimals	can store 15 decimal digits	8 bytes
float	to store floating point numbers with decimals	can store upto 7 decimal digits	4 bytes
char	to store single characters	-	2 bytes
string	to stores text	-	2 bytes per character
bool	to stores either true or false	-	1 bit

Variables

Syntax

datatype variable-name = value;

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition or set of few conditions IF-ELSE is used.

if(conditional-expression) {
   // code
} 
else {
   // code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression) {    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
...    
    
default:     
 // code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement) {
  // code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while(condition) {
 // code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {
  // code 
} while (condition);

Arrays

Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.

Syntax

data-type[] array-name;

Methods

Method is a set of statements which gets executed only when they are called. Call the method name in the main function to execute the method.

Syntax

static void method-name() 
{
  // code to be executed
}