I download V6.5 and had the same issue, I'm acually pulling the docs from BinaryArray in a SQL Server 2008 database
Attached you will find the 2 PDF files, I'm using
SQL user to load in database:
INSERT MarketRider(MarketId,StartDt,EndDt,MarketRiderDescr,AttribMatchExpression,IsActive,CreatedBy,CreatedDt,MarketRiderPDF) SELECT 1,'1/1/2012','12/31/2049 23:59:59','IL RR GOVT','[IsGovt]',1,@CreatedBy,GetDate(),* FROM OPENROWSET(BULK N'\\IES-SQLID6\QuantiShare\IL RR GOVT 09-2010 - QUANTI.pdf', SINGLE_BLOB) AS MarketRiderPDF
INSERT MarketRider(MarketId,StartDt,EndDt,MarketRiderDescr,AttribMatchExpression,IsActive,CreatedBy,CreatedDt,MarketRiderPDF) SELECT 1,'1/1/2012','12/31/2049 23:59:59','Federal Healthcare Program','[IsHealthCare] and not[IsResidential]',1,@CreatedBy,GetDate(),* FROM OPENROWSET(BULK N'\\IES-SQLID6\QuantiShare\Federal Healthcare Program Rider PSA 02-2010 - QUANTI.pdf', SINGLE_BLOB) AS MarketRiderPDF
MarketRider.GetForRequestGroup(Rg) - Returns the 2 docs as byte() from SQL Server
1 Doc has @COMPANYNAME once and the other docs has 2 instances of @COMPANYNAME, the doc with 1 instance does not fail with a null object reference the other does where there are multiple instances. It actually fails trying to update the second fragment.
Entire Code
For Each r In MarketRider.GetForRequestGroup(rg)
'add company name to each rider
Dim license As Aspose.Pdf.License = New Aspose.Pdf.License
license.SetLicense("Aspose.Pdf.lic")
Dim ms As MemoryStream = New MemoryStream(r.MarketRiderPDF)
Dim doc As New Document(ms)
Dim textFA As New Text.TextFragmentAbsorber("@COMPANYNAME")
For Each p As Page In doc.Pages
p.Accept(textFA)
For Each frag As Text.TextFragment In textFA.TextFragments
frag.Text = rg.Parent.CompanyName
Next
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