c# - MySQL 连接器打开连接时超时

Question

我有以下类(class):

public class MySqlConnectionManager
{
    public MySqlConnection Connection { get; set; }

    public void OpenConnection()
    {
        Connection = new MySqlConnection(GetConnectionString());
        try
        {
            Connection.Open();
        }
        catch (MySqlException exc)
        {
            switch (exc.Number)
            {
                case 0:
                    throw new Exception("Cannot connect to MySQL-server. Please contact administrator.");
                case 1045:
                    throw new Exception("Invalid username/password to connect to MySQL-server. Please correct data.");
                default:
                    throw new Exception("Unknown MySQL-connection error. Code: " + exc.Number);
            }
        }
    }

    private string GetConnectionString()
    {
        string activeDatabaseServer;
        string activeDatabaseName;
        string activeDatabaseUsername;
        string activeDatabasePassword;

        #if DEBUG
            activeDatabaseServer = DebugDatabaseServer;
            activeDatabaseName = DebugDatabaseName;
            activeDatabaseUsername = DebugDatabaseUsername;
            activeDatabasePassword = DebugDatabasePassword;
        #else
            activeDatabaseServer = ReleaseDatabaseServer;
            activeDatabaseName = ReleaseDatabaseName;
            activeDatabaseUsername = ReleaseDatabaseUsername;
            activeDatabasePassword = ReleaseDatabasePassword;
        #endif

        string connectionString = "server=" + activeDatabaseServer + ";uid=" + activeDatabaseUsername + ";pwd=" +
                                  activeDatabasePassword + ";database=" + activeDatabaseName + ";";

        return connectionString;
    }

调用 Connection.Open() 时，出现超时异常。将超时设置为 120 秒并没有帮助。我的调试数据库可以工作(它在本地)。我仅在 Release模式下遇到此异常。但我确信服务器名称、数据库、用户名和密码都是正确的，因为我使用的是另一个用 php 编写的应用程序中的相同数据库，一切都工作正常。

密码包含特殊字符，如“!”、“%”、“*”、“.”或者 '@'。这会造成任何麻烦吗？

Answer 1

我的代码在外部系统上运行。无法从外部连接到 1&1 托管的 mysql 数据库。 :(