Using class to retrieve data

I have a button and a gridview
on button click event :
 Dim source = New BindingSource()  DataGridView1.DataSource = GetData("SELECT * FROM  PRAMC")
 Private Shared Function GetData(ByVal selectCommand As String) As DataTable         Dim conn As String = ConfigurationManager.ConnectionStrings("CnnStr").ToString()         Dim adapter As New OracleDataAdapter(selectCommand, conn)         Dim data As New DataTable()         adapter.Fill(data)         Return data     End Function

I need to use the function in class name "getdatagrid"  and then call it when clicking on the button

please help
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