private static bool CheckDatabaseExists( string databaseName)
{

        {
            string sqlCreateDBQuery;
            bool result = false;

            try
            {
                SqlConnection tmpConn = new SqlConnection(@"Data Source=(localdb)\ProjectsV13;Initial Catalog=Example;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False;
 
");

                sqlCreateDBQuery = string.Format("SELECT database_id from sys.databases WHERE Name  = ‘{0}‘", databaseName);
        
               using (tmpConn)
                {
                    using (SqlCommand sqlCmd = new SqlCommand(sqlCreateDBQuery, tmpConn))
                    {
                        tmpConn.Open();

                        
 
object resultObj = sqlCmd.ExecuteScalar();

                        int databaseID = 0;

                        if (resultObj != null)
                        {
                            int.TryParse(resultObj.ToString(), out databaseID);
                        }

                        tmpConn.Close();

                        result 
 
= (databaseID > 0);
                    }
                }
            }
            catch (Exception ex)
            {
                result = false;
            }

            return result;
        }
}

c#檢測是否存在數據庫（SQL SERVER）