5.1.1 Creating a Connector/Net Connection String

The MySqlConnection object is configured using a connection string. A connection string contains several key/value pairs, separated by semicolons. In each key/value pair, the option name and its corresponding value are joined by an equal sign. For the list of option names to use in the connection string, see Chapter 6, Connector/Net Connection-String Options Reference.

The following is a sample connection string:

"server=127.0.0.1;uid=root;pwd=12345;database=test"

In this example, the MySqlConnection object is configured to connect to a MySQL server at 127.0.0.1, with a user name of root and a password of 12345. The default database for all statements will be the test database.

Note

Using the '@' symbol for parameters is now the preferred approach, although the old pattern of using '?' is still supported. To avoid conflicts when using the '@' symbol in combination with user variables, see the Allow User Variables connection string option in Chapter 6, Connector/Net Connection-String Options Reference. The Old Syntax connection string option has now been deprecated.

Opening a Connection

Once you have created a connection string it can be used to open a connection to the MySQL server.

The following code is used to create a MySqlConnection object, assign the connection string, and open the connection.

Connector/Net can also connect using the native Windows authentication plugin. See Section 5.4, “Using the Windows Native Authentication Plugin” for details.

You can further extend the authentication mechanism by writing your own authentication plugin. See Section 5.5, “Writing a Custom Authentication Plugin” for details.

Visual Basic Example
Dim conn As New MySql.Data.MySqlClient.MySqlConnection
Dim myConnectionString as String

myConnectionString = "server=127.0.0.1;" _
            & "uid=root;" _
            & "pwd=12345;" _
            & "database=test"

Try
  conn.ConnectionString = myConnectionString
  conn.Open()

Catch ex As MySql.Data.MySqlClient.MySqlException
  MessageBox.Show(ex.Message)
End Try
C# Example
MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString;

myConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test";

try
{
    conn = new MySql.Data.MySqlClient.MySqlConnection();
    conn.ConnectionString = myConnectionString;
    conn.Open();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message);
}

You can also pass the connection string to the constructor of the MySqlConnection class:

Visual Basic Example
Dim myConnectionString as String

myConnectionString = "server=127.0.0.1;" _
              & "uid=root;" _
              & "pwd=12345;" _
              & "database=test"

Try
    Dim conn As New MySql.Data.MySqlClient.MySqlConnection(myConnectionString)
    conn.Open()
Catch ex As MySql.Data.MySqlClient.MySqlException
   MessageBox.Show(ex.Message)
End Try
C# Example
MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString;

myConnectionString = "server=127.0.0.1;uid=root;" +
    "pwd=12345;database=test";

try
{
    conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString);
    conn.Open();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{
    MessageBox.Show(ex.Message);
}

Once the connection is open it can be used by the other Connector/Net classes to communicate with the MySQL server.