无法使用visual basic表单插入mysql数据库

Imports MySql.Data.MySqlClient

Public Class Form1
    Dim conn As MySqlConnection
    Dim connectionString As String = "server=<MySQL服务器地址>;user=<用户名>;database=<数据库名>;port=<端口号>;password=<密码>"

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        conn = New MySqlConnection(connectionString)
        Try
            conn.Open()
        Catch ex As Exception
            MessageBox.Show("无法连接到MySQL数据库：" & ex.Message)
        End Try
    End Sub

    Private Sub btnInsert_Click(sender As Object, e As EventArgs) Handles btnInsert.Click
        Dim sql As String = "INSERT INTO <表名> (column1, column2, column3) VALUES (@value1, @value2, @value3)"
        Dim cmd As New MySqlCommand(sql, conn)

        cmd.Parameters.AddWithValue("@value1", txtValue1.Text)
        cmd.Parameters.AddWithValue("@value2", txtValue2.Text)
        cmd.Parameters.AddWithValue("@value3", txtValue3.Text)

        Try
            cmd.ExecuteNonQuery()
            MessageBox.Show("数据插入成功！")
        Catch ex As Exception
            MessageBox.Show("插入数据时发生错误：" & ex.Message)
        End Try
    End Sub
End Class