问题
I have my project set to .NET Framework 4.0. When I add System.IO.Packaging, it says that it doesn't exist. It also doesn't show up when I try to add it as a reference to the project.
How can I add System.IO.Packaging to my C# project?
回答1:
According to a user comment on this MSDN page, you have to add a reference to the WindowsBase .Net library.
回答2:
For a C# solution in Visual Studio 2010 with .NET 4.0:
- In your project's Solution Explorer, right-click on References and select Add References from the context menu.
- Select Assemblies in the left-hand pane, then click the Browse button next to the File name field near the botton of the pane.
- Browse to .NET 4.0 reference assemblies and select WindowsBase.dll. For example, on my machine (Windows 7, 64-bit) the complete path is:
C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\WindowsBase.dll
Save the solution (especially if you're compiling from the command-line with MSBuild) and you should now be able to add the using System.IO.Packaging directive to the top of your .cs file without an error appearing.
回答3:
System.IO.Packaging is a namespace, not a reference. Most (all?) of the classes within the namespace, such as ZipPackage, are deployed in WindowsBase.dll.
Make sure you have a reference to WindowsBase.dll - if you do, you can just add: using System.IO.Packaging; to your .cs files, and you'll be fine.
Note that you can see this in the documentation for any class on MSDN. For example, in ZipPackage, it lists:
Namespace: System.IO.Packaging
Assembly: WindowsBase (in WindowsBase.dll)
回答4:
We can add WindowsBase.dll in Dot Net framework 3.5 as well. I am using XP machine and Path for WindowsBase.dll is
C:\Program Files\Reference Assemblies\Microsoft\Framework\.NETFramework\v3.5\Profile\Client\WindowsBase.dll
Example for using System.IO.packaging is given here -
Using System.IO.Packaging to generate a ZIP file
回答5:
The System.IO.Packaging namespace is provided by WindowsBase. When you add a reference, add WindowsBase as the reference instead of trying to find System.IO.Packaging.
回答6:
You need to add a reference to the WindowsBase.dll. System.IO.Packaging is located in there.
See this article for more details:
http://msdn.microsoft.com/en-us/library/system.io.packaging.package.aspx
回答7:
System.IO.Packaging v4.0.30319 is in WindowsBase.dll v4.0.30319
For windows 10 maybe you could found here
C:\Windows\Microsoft.NET\assembly\GAC_MSIL\WindowsBase\v4.0_4.0.0.0__31bf3856ad364e35\
回答8:
In my case I was using a ashx handler. For it to work you need to add the assembly to the project and the handler:
<%@ WebHandler Language="C#" Class="UploadExcelFile2" %>
<%@ Assembly Name="WindowsBase, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" %>
This finally worked for me, tried multiple times to add WindowsBase as reference(restarted VS, restarted machine too) but still it was not working till I added this explicitly in my aspx page. I used: <%@ Assembly Name="WindowsBase, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" %> as the dll i had referenced was version 4.0.
来源：https://stackoverflow.com/questions/7260339/system-io-packaging