PDF处理控件Aspose.Pdf的Document对象的EmbeddedFiles集合中包含了所有的附件。这个集合的每个元素代表一个FileSpecification对象。 如果你想从集合中得到一个单一的附件,你可以通过使用Index索引值来实现。Index代表被取出文件的数量。这种方式,你可以得到一个FileSpecification对象。 一旦这个对象是可用的,您就可以检索福建的所有属性或附件本身。

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下面是从PDF文件中获取单一附件的代码片段：

C#

//open document
Document pdfDocument = new Document("input.pdf");
//get particular embedded file
FileSpecification fileSpecification = pdfDocument.EmbeddedFiles[1];
//get the file properties
Console.WriteLine("Name: {0}", fileSpecification.Name);
Console.WriteLine("Description: {0}", fileSpecification.Description);
Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType);
//check if parameter object contains the parameters
if (fileSpecification.Params != null)
{
Console.WriteLine("CheckSum: {0}", 
fileSpecification.Params.CheckSum);
Console.WriteLine("Creation Date: {0}", 
fileSpecification.Params.CreationDate);
Console.WriteLine("Modification Date: {0}", 
fileSpecification.Params.ModDate);
Console.WriteLine("Size: {0}", fileSpecification.Params.Size);
}

//get the attachment and write to file or stream
byte[] fileContent = new byte[fileSpecification.Contents.Length];
fileSpecification.Contents.Read(fileContent, 0, fileContent.Length);

FileStream fileStream = new FileStream(fileSpecification.Name , FileMode.Create);
fileStream.Write(fileContent, 0, fileContent.Length);
fileStream.Close();
 

VB.NET

'open document
Dim pdfDocument As New Document("input.pdf")
'get particular embedded file
Dim fileSpecification As FileSpecification = pdfDocument.EmbeddedFiles(1)
'get the file properties
Console.WriteLine("Name: {0}", fileSpecification.Name)
Console.WriteLine("Description: {0}", fileSpecification.Description)
Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType)
'check if parameter object contains the parameters
If fileSpecification.Params IsNot Nothing Then
Console.WriteLine("CheckSum: {0}", 
fileSpecification.Params.CheckSum)
Console.WriteLine("Creation Date: {0}", 
fileSpecification.Params.CreationDate)
Console.WriteLine("Modification Date: {0}", 
fileSpecification.Params.ModDate)
Console.WriteLine("Size: {0}", fileSpecification.Params.Size)
End If

'get the attachment and write to file or stream
Dim fileContent(fileSpecification.Contents.Length - 1) As Byte
fileSpecification.Contents.Read(fileContent, 0, fileContent.Length)

Dim fileStream As New FileStream(fileSpecification.Name, FileMode.Create)
fileStream.Write(fileContent, 0, fileContent.Length)
fileStream.Close()