在Clibrary中实例化System.Xml.Serialization.XmlSerializer类的实例时，我们会看到崩溃。当尝试向字典中添加重复键时，崩溃发生在构造函数中。我在下面包括了堆栈跟踪。

此崩溃仅在一台计算机上发生，并且修复我们的.NET 3.5安装无济于事。有没有其他人看到过类似的问题？

System.ArgumentException was unhandled
  Message="Item has already been added. Key in dictionary: 'mainbuild'  Key being added: 'mainbuild'"
  Source="mscorlib"
  StackTrace:
       at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add)
       at System.Collections.Hashtable.Add(Object key, Object value)
       at System.Collections.Specialized.StringDictionary.Add(String key, String value)
       at System.CodeDom.Compiler.Executor.ExecWaitWithCaptureUnimpersonated(SafeUserTokenHandle userToken, String cmd, String currentDir, TempFileCollection tempFiles, String& outputName, String& errorName, String trueCmdLine)
       at System.CodeDom.Compiler.Executor.ExecWaitWithCapture(SafeUserTokenHandle userToken, String cmd, String currentDir, TempFileCollection tempFiles, String& outputName, String& errorName, String trueCmdLine)
       at Microsoft.CSharp.CSharpCodeGenerator.Compile(CompilerParameters options, String compilerDirectory, String compilerExe, String arguments, String& outputFile, Int32& nativeReturnValue, String trueArgs)
       at Microsoft.CSharp.CSharpCodeGenerator.FromFileBatch(CompilerParameters options, String[] fileNames)
       at Microsoft.CSharp.CSharpCodeGenerator.FromSourceBatch(CompilerParameters options, String[] sources)
       at Microsoft.CSharp.CSharpCodeGenerator.System.CodeDom.Compiler.ICodeCompiler.CompileAssemblyFromSourceBatch(CompilerParameters options, String[] sources)
       at System.CodeDom.Compiler.CodeDomProvider.CompileAssemblyFromSource(CompilerParameters options, String[] sources)
       at System.Xml.Serialization.Compiler.Compile(Assembly parent, String ns, XmlSerializerCompilerParameters xmlParameters, Evidence evidence)
       at System.Xml.Serialization.TempAssembly.GenerateAssembly(XmlMapping[] xmlMappings, Type[] types, String defaultNamespace, Evidence evidence, XmlSerializerCompilerParameters parameters, Assembly assembly, Hashtable assemblies)
       at System.Xml.Serialization.TempAssembly..ctor(XmlMapping[] xmlMappings, Type[] types, String defaultNamespace, String location, Evidence evidence)
       at System.Xml.Serialization.XmlSerializer.GenerateTempAssembly(XmlMapping xmlMapping, Type type, String defaultNamespace)
       at System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultNamespace)
       at System.Xml.Serialization.XmlSerializer..ctor(Type type)
       at OurTools.Tools.Common.XML.DataAccess`1.DeserializeFromXml(String strFilePath) in c:\AutomatedBuild\projects.0\OurTools.Tools.Common\OurTools.Tools.Common\XML\DataAcess.cs:line 100
       at OurTools.Tools.Common.ProjectFileManager.GetProjectInfoModel() in c:\AutomatedBuild\projects.0\OurTools.Tools.Common\OurTools.Tools.Common\ProjectFileManager.cs:line 252
       at OurTools.Tools.Common.ProjectFileManager.GetAvailableCultures() in c:\AutomatedBuild\projects.0\OurTools.Tools.Common\OurTools.Tools.Common\ProjectFileManager.cs:line 299
       at OurAppLib.GeneratorOptions.DefaultCultures() in c:\AutomatedBuild\projects.0\OurApp\OurAppLib\GeneratorOptions.cs:line 192
       at OurAppLib.GeneratorOptions.ReadCulturesFromArgs(List`1 arglist, String& errormsg) in c:\AutomatedBuild\projects.0\OurApp\OurAppLib\GeneratorOptions.cs:line 358
       at OurAppLib.GeneratorOptions.ReadFromArgs(String[] args, String& errormsg) in c:\AutomatedBuild\projects.0\OurApp\OurAppLib\GeneratorOptions.cs:line 261
       at OurApp.Program.Main(String[] args) in c:\AutomatedBuild\projects.0\OurApp\OurApp\Program.cs:line 76`print("code sample");`

解决方案

回答

找到此链接，它说明了问题：
http://social.msdn.microsoft.com/forums/zh-CN/asmxandxml/thread/4476f044-bab9-492d-bb94-4e0960bd2d26

快速总结：进行序列化时，该对象从所有环境变量中创建字典，但似乎在所有条目上运行ToLower()。因此，如果我们有两个除了大小写相同的环境变量，则将导致崩溃。

从像cygwin这样的系统内部运行时，这只会是一个问题，该系统对变量强制区分大小写。就我们而言，我们正在使用make。

有几种解决方案，但是它们全都围绕确保在运行capp时环境中没有任何重复的变量而设计。