How to Connect to MySQL from .NET Core

This tutorial will teach you how to connect to MySQL from .NET Core using C#.

1. Install MySqlConnector

First, install the MySqlConnector NuGet package. From a command prompt, run:

dotnet add package MySqlConnector

Or right-click your project, choose Manage NuGet Packages…, in the Search box enter MySqlConnector, and install the package in your project.

2. Connection String

A typical connection string for MySQL is:

Server=YOURSERVER;User ID=YOURUSERID;Password=YOURPASSWORD;Database=YOURDATABASE

Replace the values in that string with the appropriate settings for your database. For more advanced settings, see Connection Options.

If you are using ASP.NET Core, your connection string will usually be stored in appsettings.json:

{
  ....
  "ConnectionStrings": {
    "Default": "Server=YOURSERVER;User ID=YOURUSERID;Password=YOURPASSWORD;Database=YOURDATABASE"
  }
}

3. Configure Service (ASP.NET Core)

If using ASP.NET Core, you will want to register a database connection in Program.cs:

Recommended Install MySqlConnector.DependencyInjection via dotnet add package MySqlConnector.DependencyInjection. Then add the following to Program.cs:

builder.Services.AddMySqlDataSource(builder.Configuration.GetConnectionString("Default")!);

Alternatively, register a transient MySqlConnection object explicitly:

builder.services.AddTransient<MySqlConnection>(_ =>
    new MySqlConnection(builder.Configuration.GetConnectionString["Default"]));

The advantage of using AddMySqlDataSource is that it will automatically integrate with logging, and also register DbDataSource and DbConnection with the service collection.

4. Open and Use the Connection

In ASP.NET Core, the MySqlConnection object will be dependency-injected into your Controller class. For other kinds of projects, you may need to explicitly create the connection:

using var connection = new MySqlConnection(yourConnectionString);

You can then open the connection and execute a query:

await connection.OpenAsync();

using var command = new MySqlCommand("SELECT field FROM table;", connection);
using var reader = await command.ExecuteReaderAsync();
while (await reader.ReadAsync())
{
    var value = reader.GetValue(0);
    // do something with 'value'
}