Connect MySQL to ASP.Net Web App

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Revision as of 20:23, 8 October 2024 by Admin (talk | contribs) (Insert data)
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Install MySQL.Data

Using the Nuget Package Manager install the following:

  • MySql.Data;
  • MySql.Data.MySqlClient;

Creating the connection

Now using the page you want to connect, open the Model `cs` code.

At the top add the following

using MySql.Data;
using MySql.Data.MySqlClient;

Just for this example we will be retrieving the details from the user table, so I created this class to store each record, it should be inside the subclass of `PageModel` :

public class User
{
    public string username { get; set; }
    public string password { get; set; }
    public int status { get; set; }
}

Next I created a list of User to store the retrieved data, it should be inside the subclass of `PageModel`:

public static List<User> users = new List<User>();


I have also created this string for the connection string, it should be inside the subclass of `PageModel`:

string connection = "server=localhost;user=root;database=test;port=3306;password=usbw;";

Finally I created this method to get the connection, it should be inside the subclass of `PageModel`:

        public MySqlConnection GetConnection 
        {
            get
            {
                return new MySqlConnection(connection);
            }
        }

Getting the data

Now, in the constructor method I have added the following code:

public IndexModel(ILogger<IndexModel> logger)
{
    _logger = logger;

    users.Clear(); // clear users before a load or reload

    using var connection = GetConnection; // this gets the connection

    connection.Open(); // you must open the connection
            
    using var Command = new MySqlCommand("SELECT * FROM test;", connection ); // you can add your SQL into a command
    using var reader = Command.ExecuteReader(); // you execute the query
    while (reader.Read())
    {
         User temp = new User(); // create user
         temp.username = reader.GetString(0);
         temp.password = reader.GetString(1);
         temp.status = reader.GetInt32(2);
         users.Add(temp); // add user to list
    }
}

Insert data

Inside your subclass of `PageModel` add the following method, this will run a submit:

public IActionResult OnPost()
{
     User temp = new User();
     temp.username = Request.Form["user"];
     temp.password = Request.Form["password"];
     temp.status = Convert.ToInt32(Request.Form["status"]);

     using var connection = GetConnection;

     connection.Open();
     string sql = "insert into test values(@p1, @p2, @p3);";
     using var Command = new MySqlCommand(sql, connection);
     Command.Parameters.AddWithValue("@p1", temp.username);
     Command.Parameters.AddWithValue("@p2", temp.password);
     Command.Parameters.AddWithValue("@p3", temp.status);

     Command.ExecuteNonQuery();
     connection.Close();
	
     users.Add(temp);

     return Page();
}

In your html you need to create a form like this:

<form method="post"> <input type="Text" name="user"> <input type="Text" name="password"> <input type="number" name="status"> <input type="submit"> </form>