Question

我正在尝试连接到数据库，但它不起作用......

代码：

        Dim conn As MysqlConnection

    conn = New Mysqlconnection()
    conn.ConnectionString = "server=http://www.*****.net/phpMyAdmin; user id=*****; password=****; database=login"

    Try
        conn.Open()
    Catch myerror As MySqlException
        MsgBox("Error connecting to database!")
    End Try

它总是说错误连接到数据库！

有什么问题？

Answer 1

您无法使用http://www.*****.net/phpMyAdmin作为服务器名称。它应该只是您的域名（主机名）mydomain.com或IP地址192.168.0.10

它应如下所示：

Dim conn As MySqlConnection = New MySqlConnection
conn.ConnectionString = "Host=192.168.0.10;user=root;password=root"
conn.Open()

Answer 2

首先确保安装了MySQL Connector / NET。检查所有凭据是否正确。然后试试这个片段。

    Imports MySql.Data.MySqlClient
Public Class MySQLConnect
    Private db_con As New MySqlConnection
    Private Sub connect()
        Dim dbname As String = "DBNAME"
        Dim dbhost As String = "localhost"
        Dim user As String = "root"
        Dim pass As String = "DBPASSWORD"


        If Not db_con Is Nothing Then db_con.Close()
        db_con.ConnectionString = String.Format("server={0}; user id={1}; password={2}; database={3}; pooling=false", dbhost, user, pass, dbname)

        Try
            db_con.Open()
        Catch ex As MySqlException
            MsgBox("Database Error:[" & ex.Message & "]")
        End Try
    End Sub
End Class

试试this link，这非常直接。

Answer 3

Imports System.Data.SqlClient
Imports MySql.Data.MySqlClient
Public Class LoginForm1
    Dim mysqlconnection As MySqlConnection

    Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click
        mysqlconnection = New MySqlConnection
        mysqlconnection.ConnectionString = "server=servername.com;port=portnum;user id=username ;pwd=password;database=databasename"
        'mysqlconnection.Open()
        Try
            mysqlconnection.Open()
        Catch myerror As MySqlException
            MsgBox("Error connecting to database!")
            Exit Sub
        End Try
        MsgBox("connected to database!")
    End Sub

Mysql数据库连接vb.net

3 个答案: