Question

I have a windows application form where an IP can be input in order to connect to MySQL database. The help I need is how to program, so that if input IP doesn’t exist or doesn’t respond my form should return a message and connect to default IP i.e., localhost.

Answer 1

You could try something like this :

MySqlConnection connection;

if (this.TryConnect("xxx.xxx.xxx.xxx", out connection))
{
    // display error message here   
}
else if (this.TryConnect("localhost", out connection))
{
    // code here
}

and here’s what the TryConnect function looks like :

public bool TryConnect(string ServerIP, out MySqlConnection connection)
{
    try
    {
        const string connectionString = "Server={0};Database=<database>;Uid=<username>;Pwd=<password>;";
        var conn = new MySqlConnection(string.Format(connectionString, ServerIP));

        conn.Open();
        conn.Close();
        connection = conn;
        return true;
    }
    catch (Exception)
    {
        connection = null;
        return false;
    }
}