samples/snippets/standard/data/sqlite/HelloWorldSample/Program.cs - main - aprogrammer/dotnet-docs

samples/snippets/standard/data/sqlite/HelloWorldSample/Program.cs

85 строк2 KB

Andy De George

Move snippets from samples repo to this repo (#17296)

03 мар 2020, 19:23

03 мар 2020, 19:23dbbeda1

using System;
using System.IO;
using Microsoft.Data.Sqlite;

namespace HelloWorldSample
{
    class Program
    {
        static void Main()
        {
            using (var connection = new SqliteConnection("Data Source=hello.db"))
            {
                connection.Open();

                var command = connection.CreateCommand();
                command.CommandText =
                @"
                    CREATE TABLE user (
                        id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                        name TEXT NOT NULL
                    );

                    INSERT INTO user
                    VALUES (1, 'Brice'),
                           (2, 'Alexander'),
                           (3, 'Nate');
                ";
                command.ExecuteNonQuery();

                Console.Write("Name: ");
                var name = Console.ReadLine();

                #region snippet_Parameter
                command.CommandText =
                @"
                    INSERT INTO user (name)
                    VALUES ($name)
                ";
                command.Parameters.AddWithValue("$name", name);
                #endregion
                command.ExecuteNonQuery();

                command.CommandText =
                @"
                    SELECT last_insert_rowid()
                ";
                var newId = (long)command.ExecuteScalar();

                Console.WriteLine($"Your new user ID is {newId}.");
            }

            Console.Write("User ID: ");
            var id = int.Parse(Console.ReadLine());

            #region snippet_HelloWorld
            using (var connection = new SqliteConnection("Data Source=hello.db"))
            {
                connection.Open();

                var command = connection.CreateCommand();
                command.CommandText =
                @"
                    SELECT name
                    FROM user
                    WHERE id = $id
                ";
                command.Parameters.AddWithValue("$id", id);

                using (var reader = command.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        var name = reader.GetString(0);

                        Console.WriteLine($"Hello, {name}!");
                    }
                }
            }
            #endregion

            // Clean up
            File.Delete("hello.db");
        }
    }
}