通过 URLDownloadToFile 自动下载 PDF

Question

如何在以下代码中从网站中提取 PDF 的默认名称，而不是 blah.pdf？

Option Explicit 

Private Declare Function URLDownloadToFile Lib "urlmon" _ 
Alias "URLDownloadToFileA" ( _ 
ByVal pCaller As Long, _ 
ByVal szURL As String, _ 
ByVal szFileName As String, _ 
ByVal dwReserved As Long, _ 
ByVal lpfnCB As Long _ 
) As Long 

Sub z() 

    Dim strSource As String 
    Dim strDest As String 
    strSource = "http://www.cran.r-project.org/doc/manuals/R-intro.pdf" 
    strDest = "c:\temp\blah.pdf" 
    URLDownloadToFile 0, strSource, strDest, 0, 0 

End Sub

Answer 1

使用您原来下载文件的方法很好，但您实际上是如何确定路径和文件名的？你有清单吗？你需要从网站上获取吗？关于检索仪器编号，首先将引用（VBE > 工具 > 引用）设置为 Microsoft XML、vx.0 和 Microsoft HTML 对象库，然后相应地更改指定的 URL，然后尝试...

Option Explicit

Sub GetInstrumentNumber()

    'Set a reference (VBE > Tools > References) to the following libraries:
    '   1) Microsoft XML, v6.0 (or whatever version you have)
    '   2) Microsoft HTML Object Library

    Dim XMLReq As New MSXML2.XMLHTTP60
    Dim HTMLDoc As New MSHTML.HTMLDocument
    Dim sURL As String
    Dim sInstrument As String

    sURL = "http://www.cran.r-project.org/..." 'change the URL adddress accordingly

    With XMLReq
        .Open "GET", sURL, False
        .send
        Do While .readyState <> 4
            DoEvents
        Loop
    End With

    If XMLReq.Status <> 200 Then
        MsgBox "Error " & XMLReq.Status & ":  " & XMLReq.statusText
        Exit Sub
    End If

    HTMLDoc.body.innerHTML = XMLReq.responseText

    sInstrument = HTMLDoc.getElementById("6063270").getElementsByTagName("tr")(0).Cells(0).innerText
    sInstrument = Trim(Split(sInstrument, ":")(1))

    MsgBox "Instrument number:  " & sInstrument, vbInformation

    Set XMLReq = Nothing
    Set HTMLDoc = Nothing

End Sub