印出來是空白的，請問該如何指定給我的 A3 PDF呢?
Public Class myform
Private WithEvents pdoc As New Drawing.Printing.PrintDocument
Dim a4Index As Integer = -1

Private Sub myform_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

    'setup printer
    PrintDocument1.PrinterSettings.PrinterName = "HP LaserJet Professional P1106"

    'find A4
    For i As Integer = 0 To pdoc.PrinterSettings.PaperSizes.Count - 1
        If PrintDocument1.PrinterSettings.PaperSizes(i).PaperName = "A5" Then
            a4Index = i
            Exit For
        End If
    Next
End Sub

Private Sub PrintDocument1_QueryPageSettings(ByVal sender As Object, ByVal e As Printing.QueryPageSettingsEventArgs) Handles PrintDocument1.QueryPageSettings
    'e.PageSettings.PaperSource = Me.pdoc.PrinterSettings.PaperSources(a4Index)
    e.PageSettings.PaperSize = Me.pdoc.PrinterSettings.PaperSizes(a4Index)
End Sub

Private Sub PrintDocument1_PrintPage(ByVal sender As System.Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
End Sub

Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
    PrintDocument1 = "C:\Users\Administrator\AppData\Local\Temp\1\E.pdf"
    'Me.PrintPreviewDialog1.Document = PrintDocument1
    'Me.PrintPreviewDialog1.ShowDialog()
    Me.PrintDocument1.Print()
End Sub

End Class

公司的印表機只能印A4，但是客戶那邊的印表機，可以印A3和A4

了解，上網查了一下有PrintDocument,PrinterSettings,PageSettings,PaperSize,PageSetupDialog1，已眼花，盲目試了一下都沒有成果，請問該如何用程式碼將紙張改成A3或A5並印出來呢?

答案是，不可能。

我想你完全不了解我說的意義。
我用另外一種情況來問你好了。

能否在一片dvd片(4g)。來去燒錄藍光映像檔(8g)。
想也知道不可能。除非用特殊的方式。分片燒錄處理。

設備的縮放一般是屬於本機端在控管，基於「本機安全性原則」的原理。沒經過特別的管道。任何一個遠端應用語言(大多數指的是網頁程式)都不得去控制本機不被允許的東西。