使用MySql子连接到数据库 - 无法连接到任何主机

Question

我正在研究MySql .NET连接器类的包装器。到目前为止，它已正常工作，没有缺陷。但是，我必须改变一些东西，因为它根本不会连接到我的MySql服务器，我可以通过phpMyAdmin访问服务器。

现在，我有以下代码：

Public Function Connect(ByVal Host As String,
                        ByVal Database As String,
                        ByVal Username As String,
                        ByVal Password As String) As Boolean
    Try
        _ConnInfo.Host = Host
        _ConnInfo.Username = Username
        _ConnInfo.Password = Password
        _ConnInfo.Database = Database
        _ConnInfo.ConnectionString = String.Format("server={0}; user id={1}; password={2}; database={3}; pooling=false",
                                                   _ConnInfo.Host,
                                                   _ConnInfo.Username,
                                                   _ConnInfo.Password,
                                                   _ConnInfo.Database)
        _mysqlConn.ConnectionString = _ConnInfo.ConnectionString
        _mysqlConn.Open()
        CreateEventArgs(eArgs, currentID, False, "Open Connection", _ConnInfo, Me, MySQL_Wrapper_Operation.Connect, Nothing)
        RaiseEvent OperationCompleted(eArgs)
        OnConnect()
        Return True
    Catch ex As Exception
        OnConnectError(ex)
        CreateEventArgs(eArgs, currentID, True, "Open Connection", _ConnInfo, Me, MySQL_Wrapper_Operation.Connect, Nothing, ex)
        RaiseEvent OperationCompleted(eArgs)
        Return False
    End Try
End Function

_ConnInfo是用于存储MySql连接信息的类的实例：

Public Class MySQL_Wrapper_ConnectionInfo
    Public Sub New()

    End Sub
    Public Sub New(ByVal _Host As String,
                   ByVal _Database As String,
                   ByVal _Username As String,
                   ByVal _Password As String,
                   Optional ByVal _ConnectionString As String = "")
        Host = _Host
        Database = _Database
        Username = _Username
        Password = _Password
        ConnectionString = _ConnectionString
    End Sub
    Public Host As String
    Public Database As String
    Public Username As String
    Public Password As String
    Public ConnectionString As String
End Class

无论如何，当我调用Connect("10.131.120.46", "studenttest", "studenttest", "********")时，我的函数返回false，我得到的错误是：

  

无法连接到任何指定的MySQL主机。

我尝试使用另一个连接字符串来自here：

    _ConnInfo.ConnectionString = $"Server={_ConnInfo.Host};Database={_ConnInfo.Database};Uid={_ConnInfo.Username};Pwd={_ConnInfo.Password};Pooling=False;"

以上给出了相同的结果。在运行时，我能够找到连接字符串，即：

  

服务器= 10.131.120.46; user id = studenttest;密码= ********;数据库= studenttest;池=假

我只想指出错误发生在_mysqlConn.Open()（其中_mysqlConn在类中声明为Private Property _mysqlConn As New MySqlConnection。

如果有人能在我犯错的地方给我一个头脑，我会非常感激。

提前致谢。