解决VisualStudio找不到对nunit.framework.dll的引用

【问题描述】

我有一个VisualStudio 2008的工程，它引用了Assembly nunit.framework.dll，以便进行单元测试。当我用一个帐号登录机器，用VS20008打开这个工程，在工程的References下面能够找到，VS能够找到对nunit.framework.dll的引用。但是，当我用另外一个帐号登录机器是，再用VS20008打开这个工程，在工程的References下面的nunit.framework前面出现了一个黄色的惊叹号，它表示VS没有找到对nunit.framework.dll的引用。这是为什么呢？

【问题解决】

1. 首先要弄清楚VS是如何去查找应用的Assembly的。

VS在build工程的时候，是调用msbuild来完成的。所以，VS查找Assembly的方法与msbuild查找的方法是一样的。这样，我们通过直接调用msbuild来build这个工程，然后分析日志文件就能找到原因。在这里，我们需要使用到msbuild的一个参数：/verbosity:level（见参考1）。level包含这几种：q[uiet], m[inimal], n[ormal], d[etailed], and diag[nostic]。这里我们需要使用到最后一种，也是给出信息最多的一种，它是 diag[nostic]。例如：

c:\temp> msbuild /verbosity:diag test.csproj >output.log

运行完这条命令，会在c:\temp下生成output.log。分析这个文件，我们就能够知道VS到底会在哪些目录下查找nunit.framework.dll。

以下是我给出的两份output.log文件中有关查找nunit.framework.dll的部分：

1）build成功的output.log

Primary reference "nunit.framework, Version=2.6.1.12217, Culture=neutral, PublicKeyToken=96d09a1eb7f44a77". (TaskId:89)

Resolved file path is "C:\Program Files (x86)\NUnit 2.6.1\bin\framework\nunit.framework.dll". (TaskId:89)

Reference found at search path location "{Registry:Software\Microsoft\.NetFramework,v3.5,AssemblyFoldersEx}". (TaskId:89)

For SearchPath "{CandidateAssemblyFiles}". (TaskId:89)

......

For SearchPath "{TargetFrameworkDirectory}". (TaskId:89)

Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\nunit.framework.exe", but it didn't exist. (TaskId:89)

Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.5\nunit.framework.dll", but it didn't exist. (TaskId:89)

Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.0\nunit.framework.exe", but it didn't exist. (TaskId:89)

Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.0\nunit.framework.dll", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v3.5\nunit.framework.exe", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v3.5\nunit.framework.dll", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v3.0\nunit.framework.exe", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v3.0\nunit.framework.dll", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v2.0.50727\nunit.framework.exe", but it didn't exist. (TaskId:89)

Considered "C:\Windows\Microsoft.NET\Framework\v2.0.50727\nunit.framework.dll", but it didn't exist. (TaskId:89)

For SearchPath "{Registry:Software\Microsoft\.NetFramework,v3.5,AssemblyFoldersEx}". (TaskId:89)

Considered "C:\Program Files (x86)\NUnit 2.6.1\bin\framework\nunit.framework.exe", but it didn't exist. (TaskId:89)

Found related file "C:\Program Files (x86)\NUnit 2.6.1\bin\framework\nunit.framework.xml". (TaskId:89)

2）build失败的output.log

Primary reference "nunit.framework, Version=2.6.1.12217, Culture=neutral, PublicKeyToken=96d09a1eb7f44a77, processorArchitecture=MSIL". (TaskId:89)

C:\Windows\Microsoft.NET\Framework\v3.5\Microsoft.Common.targets : warning MSB3245: Could not resolve this reference. Could not locate the assembly "nunit.framework, Version=2.6.1.12217, Culture=neutral, PublicKeyToken=96d09a1eb7f44a77, processorArchitecture=MSIL". Check to make sure the assembly exists on disk. If this reference is required by your code, you may get compilation errors.