使用 SSH.NET 库从 .NET 连接到 MySQL
问题：
An ASP.NET/C# 网页尝试使用 Renci.SshNet 和 mysql-connector-net 库通过 SSH 连接查询远程服务器上的 MySQL 数据库。但是，代码并未从数据库中检索任何数据。
代码片段：
C# 代码尝试建立 SSH 连接、转发端口和然后连接MySQL数据库。但是，它无法从数据库中检索任何数据。
<code class="csharp">using(var client = new SshClient("ssh server id", "sshuser", "sshpassword")) // establishing ssh connection to server where MySql is hosted
{
client.Connect();
if (client.IsConnected)
{
var portForwarded = new ForwardedPortLocal("127.0.0.1", 3306, "127.0.0.1", 3306);
client.AddForwardedPort(portForwarded);
portForwarded.Start();
using (MySqlConnection con = new MySqlConnection("SERVER=127.0.0.1;PORT=3306;UID=someuser;PASSWORD=somepass;DATABASE=Dbname"))
{
using (MySqlCommand com = new MySqlCommand("SELECT * FROM cities", con))
{
com.CommandType = CommandType.CommandText;
DataSet ds = new DataSet();
MySqlDataAdapter da = new MySqlDataAdapter(com);
da.Fill(ds);
foreach (DataRow drow in ds.Tables[0].Rows)
{
Console.WriteLine("From MySql: " + drow[1].ToString());
}
}
}
client.Disconnect();
}
else
{
Console.WriteLine("Client cannot be reached...");
}
}</code>解决方案：
要解决此问题，可以对代码进行以下修改：
MySqlConnectionStringBuilder connBuilder = new MySqlConnectionStringBuilder(); connBuilder.AllowBatch = true; connBuilder.Server = "portal.RemoteServer.edu"; connBuilder.Port = 3306; connBuilder.UserID = "RemoteServerUsername"; connBuilder.Password = "RemoteServerPassword"; connBuilder.Database = "DatabaseName";
修改代码：
<code class="csharp">using(var client = new SshClient("portal.RemoteServer.edu", "RemoteServerUsername", "RemoteServerPassword")) // establishing ssh connection to server where MySql is hosted
{
client.Connect();
if (client.IsConnected)
{
var portForwarded = new ForwardedPortLocal("127.0.0.1", 3306, "127.0.0.1", 3306);
client.AddForwardedPort(portForwarded);
portForwarded.Start();
using (MySqlConnection con = new MySqlConnection(connBuilder.ConnectionString))
{
using (MySqlCommand com = new MySqlCommand("SELECT * FROM Clients", con))
{
com.CommandType = CommandType.CommandText;
DataSet ds = new DataSet();
MySqlDataAdapter da = new MySqlDataAdapter(com);
da.Fill(ds);
foreach (DataRow drow in ds.Tables[0].Rows)
{
Console.WriteLine("From MySql: " + drow[1].ToString());
}
}
}
client.Disconnect();
}
else
{
Console.WriteLine("Client cannot be reached...");
}
}</code>以上是以下是几个符合文章内容的英文问答类标题： * Why Am I Unable to Retrieve Data from a MySQL Database Through SSH.NET? * Troubleshooting MySQL Connection Issues with SSH.NET: A Case Study * How to Correctly Connect to a Rem的详细内容。更多信息请关注PHP中文网其他相关文章！
