Inconsistent accessibility on class [duplicate]

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Inconsistent accessibility problem [duplicate] (3 answers)

Closed 8 years ago.

I am getting the following error

Error Inconsistent accessibility: field type 'Project3_MineSweeper.DB' is less accessible than field 'Project3_MineSweeper.Form2.db'

Here is the code in DB.cs

class DB
{
    private string connectionString;

    public string ConnectionString
    {
        get { return connectionString; }
    }

    private SqlConnection connection;

    public SqlConnection Connection
    {
        get { return connection; }
    }

    public DB()
    {
        connectionString="Data Source=NGFAJAR-PC\\FAJAR;Initial Catalog=DB;Integrated Security=True";
        connection = new SqlConnection(connectionString);
    }
}

And this is the code of Form2.cs

public partial class Form2 : Form
{
    public DB db; //it's here where I am getting the error

    private Form3 form3;
    public Form2()
    {
        db = new DB();
        InitializeComponent();
    }
    ...
}

Lastly, Form3.cs

public partial class Form3 : Form
{
    private Form2 form2;
    public Form3()
    {
        InitializeComponent();
    }

    public void loadData()
    {
        DataTable dt = form2.db.GetData();
        dgvScore.DataSource = dt;
    }
}

What's wrong? And what should I do to fix it? Thanks for your appreciated attention and help.

Answer 1

You need to declare class DB as internal class DB or public class DB.

Answer 2

What's wrong?

The type DB is declared as class DB with no explicit access modifier. This is probably good. Then the default accessibility for a direct member of a namespace (Project3_MineSweeper), is internal. So DB is an internal class.

Now Form2 is a public class. Public means that anyone, even code outside this "program" (this assembly) can see Form2. Now Form2 has a field db which is also public. So db is public inside a public class, so db can be seen from the outside. But here's the problem: People outside your program don't even know there's a type called Project3_MineSweeper.DB. So how can they see a field of a "secret" type? Here's the inconsistency.

And what should I do to fix it?

Make the accessibilities compatible, for example be changing the field to internal, so:

public partial class Form2 : Form
{
    internal DB db;

    ...
}

Answer 3

Change you DB class like so

public class DB
{
    ....
}