I've created a class called connector. By clicking on project and adding a class开发者_如何学C. And I want to inherit from that class in the forms But I get this error.
Base class '<baseclassname1>' specified for class '<partialclassname>' cannot be different from the base class '<baseclassname2>' of one of its other partial types`
what do I do? Here's the class named connect.vb: Imports MySql.Data.MySqlClient
Public Class connect
Private dataAdapter As New MySqlDataAdapter()
Dim dr As MySqlDataReader
Dim ds As New DataSet
Dim con As New MySql.Data.MySqlClient.MySqlConnection
Dim dsNewRow As DataRow
Dim cmd As MySqlCommand
Dim cn As MySqlConnection
Dim da As MySql.Data.MySqlClient.MySqlDataAdapter
End Class
And I'm trying to inherit it from this one, which is a form:
Public Class AdminForm
Inherits connect
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
cn = New MySqlConnection("Server=localhost; Database=testing;Uid=root;Pwd=password;")
'provider to be used when working with access database
cn.Open()
cmd = New MySqlCommand("select * from student", cn)
End Sub
End Class
Please help
.NET does not support multiple inheritance. Your form (WinForm or ASP.NET) already derives from a base class which means that you cannot have it derived from your base class. The actions you could take to fix this problem will largely depend on what you are trying to achieve.
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