default.aspx code
<asp:FileUpload runat="server" id="fileUpload1" Multiple="Multiple">
</asp:FileUpload>
<asp:Button runat="server" Text="Upload Files" id="uploadBtn"/>
default.aspx.vb
Protected Sub uploadBtn_Click(sender As Object, e As System.EventArgs) Handles uploadBtn.Click
Dim ImageFiles As HttpFileCollection = Request.Files
For i As Integer = 0 To ImageFiles.Count - 1
Dim file As HttpPostedFile = ImageFiles(i)
file.SaveAs(Server.MapPath("Uploads/") & file.FileName)
Next
End Sub