我创建运行MS SQL亚马逊AWS RDS实例。我已经成功地之所以能在C＃中使用以编程方式创建数据库：

I've created an Amazon AWS RDS instance running MS SQL. I've successfully been able to programmatically create a database in C# using:

SqlConnection myConn = new SqlConnection("Data Source=<public-ip-name>;Persist Security Info=True;User ID=<userid>;PWD=<pwd>;");
myConn.Open();
string str = "CREATE DATABASE contacts";
SqlCommand cmd = new SqlCommand(str, myConn);
cmd.ExecuteNonQuery();

不过，我一直没能做出更复杂的连接字符串的工作：

However, I haven't been able to make a more complex connection string work:

        str = "CREATE DATABASE contacts ON PRIMARY " +
            "(NAME = Contacts_Data, " +
            @"FILENAME = 'c:\contacts.mdf', " +
            "SIZE = 4MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
            "LOG ON (NAME = Contacts_Log, " +
            @"FILENAME = 'c:\contacts.ldf', " +
            "SIZE = 1MB, " +
            "MAXSIZE = 5MB, " +
            "FILEGROWTH = 10%)";

错误（5）似乎抱怨C：\不能写入。也许它不存在？如果我省略了文件名，错误抱怨我忽略它。什么是文件名，正确的价值？看来，文件名必须指定现有文件的路径。

The error (5) seems to complain that C:\ can't be written to. Perhaps it doesn't exist? If I omit FILENAME, an error complains that I omitted it. What is the correct value for FILENAME? It appears that FILENAME must specify an existing file path.

推荐答案

我有codeD jtseng的答案在C＃

I've coded jtseng's answer in C#

static string GetDBPath(SqlConnection myConn, string db = "master")
{
  string sqlstr = "USE " + db + "; EXEC sp_helpfile";
  SqlCommand command = new SqlCommand(sqlstr, myConn);
  SqlDataReader reader = command.ExecuteReader(CommandBehavior.SingleRow);
  reader.Read();
  string filename = reader["filename"].ToString();
  string directory = System.IO.Path.GetDirectoryName(filename);
  return directory;
}

通过名为：

SqlConnection myConn = new SqlConnection("Data Source=<public ip>;Persist Security Info=True;User ID=<userid>;PWD=<pwd>;");
myConn.Open();
string dbPath = GetDBPath(myConn); // default db is master