Notes

using MySql.Data.MySqlClient;
using System;

internal class FullExample
{
MySqlConnection connection;
MySqlCommand command;
public void CreateConnection()
{
string connectionString = "datasource=localhost;port=3306" +
";username=root;password=";
connection = new MySqlConnection(connectionString);
connection.Open();
Console.WriteLine("Connection established successfully.");
}
public void InsertIntoDB(string SqlQuery)
{
command = new MySqlCommand(SqlQuery, connection);
command.ExecuteNonQuery();
Console.WriteLine("**************************n Operation performed Sucessfully");
}

}
internal class UpdateExample
{
MySqlConnection connection;
MySqlCommand command;

public void CreateConnection()
{
string connectionString = "datasource=localhost;port=3306" +
";username=root;password=";
connection = new MySqlConnection(connectionString);
connection.Open();
Console.WriteLine("Connection established successfully.");
}
public void UpdateIntoDB(string SqlQuery)
{
command = new MySqlCommand(SqlQuery, connection);
command.ExecuteNonQuery();
Console.WriteLine("**************************n Operation performed Sucessfully");
}


}
class Program {

public static void Main(string[] args)
{
/*FullExample Example = new FullExample();*/
UpdateExample Example = new UpdateExample();

try
{
Example.CreateConnection();
x: Console.WriteLine("1. Insertt 2.Update t 3.Deletet 4.Selectt");
Console.WriteLine("Enter your choice");
int n =Convert.ToInt32(Console.ReadLine());
string sql = "", firstName = "", lastName = "";
int id = 0, regNo;
Console.WriteLine("Enter the id which you want to change");
id =int.Parse(Console.ReadLine());
Console.WriteLine("Enter first name of student");
firstName = Console.ReadLine();
Console.WriteLine("Enter last name of student");
lastName = Console.ReadLine();
Console.WriteLine("Enter reg no of student");
regNo =int.Parse( Console.ReadLine());
Console.WriteLine("--------------------------Succesfully Updated student's data-------------------------");
string sqlQuery = "UPDATE college.students SET reg_id = " + regNo + ", first_name = '" + firstName + "', last_name = '" + lastName + "' WHERE id = " + id;
Example.UpdateIntoDB(sqlQuery);
/*Console.WriteLine("--------------------------Succesfully inserted student's data-------------------------");
string sqlQuery = "INSERT INTO college.students (reg_id, first_name, last_name) VALUES (" + regNo + ", '" + firstName + "', '" + lastName + "')";
Example.InsertIntoDB(sqlQuery);*/
/* switch (n)
{
case 1:
Console.WriteLine("Enter First name of student");
} */
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}

}
}