要全文查找上传的pdf文件中的关键词，该怎么做？

呃，pdf比较麻烦的，要有第三方dll才能读取内容。

mark 读取pdf内容

Dim reader As New iTextSharp.text.pdf.PdfReader("d:\\test.pdf")

Dim n As Integer = reader.NumberOfPages
Dim str As String = ""
For i As Integer = 1 To n
    Dim strategy As object = New iTextSharp.text.pdf.parser.SimpleTextExtractionStrategy()
    Dim currentText As String = iTextSharp.text.pdf.parser.PdfTextExtractor.GetTextFromPage(Reader, i, strategy)
   
    currentText = Encoding.UTF8.GetString(ASCIIEncoding.Convert(Encoding.[Default], Encoding.UTF8, Encoding.[Default].GetBytes(currentText)))
    str &= currentText
   
Next
msgbox(str)
reader.Close()

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