Invalid Serialized File Header Unity

Christoph Schittko May 2004 Applies to: Microsoft® Visual Studio®.NET Summary: Christoph Schittko discusses various techniques for diagnosing common problems that occur when converting XML to objects and vice versa with XML Serialization technology in the.NET Framework. (13 printed pages) Contents Introduction The XmlSerializer in the.NET Framework is a great tool to map strongly structured XML data to.NET objects.

The XmlSerializer performs the transformations between XML documents and objects in your program with a single API call. The mapping rules for the transformation are expressed in the.NET classes via metadata attributes. This programming model comes with its own class of errors that developers need to learn how to diagnose. For example, the metadata attributes have to describe all variations of an XML format that a serializer can process. This article examines the various errors that can occur when building XML based solutions with the XmlSerializer, and discusses techniques and tools to diagnose them. The Inner Workings of the XmlSerializer It is important to understand what is going on under the covers of the very simple interface of XmlSerializer in order to effectively troubleshoot problems arising from XML serialization.

Redis scripting has support for MessagePack because it is a fast and compact serialization format with a simple to implement specification. I liked it so much that I. Hi, I've recently been getting this error >Invalid serialized file header. File:'Assets/Scenes/Aridia/Scene 1.unity'. I can't figure out whats.

In contrast to traditional parsing paradigms, the XmlSerializer from the namespace in the.NET Framework binds XML documents to instances of.NET classes. Instead of writing DOM or SAX parsing code, programmers declaratively set up binding rules by attaching.NET metadata attributes directly in the classes. Since all the parsing rules are expressed through the attributes, interface of the XmlSerializer is very simple.

It consists primarily of two methods, to produce XML from an object instance, and to parse an XML document into an object graph. This approach works very well in situations with strongly typed, rigidly structured XML formats that map well to programming objects. If a format is defined by a that consists of complexTypes without mixed content or an excessive use wildcards ( xs:any and xs;anyAttribute), then XML serialization is a good approach to process that data. Message oriented applications are a very good example in which the format of the exchange between applications is defined up front.

Because many message driven enterprise applications have very high throughput requirements, the Serialize() and Deserialize() methods are designed to be very fast. In fact, the XmlSerializer is what powers the highly scalable libraries in the namespace, and. The trade-off for the high performance of the XmlSerializer is two-fold. The first is flexibility with regards to the XML formats a given can process, and the second is a rather processing intensive instance construction. When you instantiate an XmlSerializer you have to pass the of the objects that you will attempt to serialize and deserialize with that serializer instance. The serializer examines all public fields and properties of the Type to learn about which types an instance references at runtime. It then proceeds to create C# code for a set of classes to handle serialization and deserialization using the classes in the namespace.

During this process, the XmlSerializer checks the reflected type for to customize the created classes to the XML format definition. These classes are then compiled into a temporary assembly and called by the Serialize() and Deserialize() methods to perform the XML to object conversions. This elaborate process to set up the XmlSerializer and the declarative programming model result in three classes of errors, some of which can be complicated to troubleshoot: • The generated serialization classes expect the objects serialized to fully conform to the type structure defined by the metadata attributes. An object will fail to serialize if the XmlSerializer encounters any types that were not declared, either explicitly or via an XML serialization attribute.

• An XML document fails to deserialize if its root element does not map an object type; when the document is not well formed, such as if it contains characters illegal according to the; and in some cases if the document violates restrictions of the underlying schema. • Finally, the creation of the serialization classes and their subsequent compilation may fail for a number of different reasons. The creation of the classes can fail when the type passed to the constructor or a type that is referenced by that type implements an unsupported interface or does not satisfy the limitations imposed by the. Nv Dvr Cd Key there. The compilation step can fail when the attached attributes produce C# code that cannot be compiled, or also due to security related reasons. The following sections will examine these cases in more depth and offer guidance and suggestions on how to solve them.

Serialization Errors The first class of errors we examine occurs in the Serialize() method. It occurs when the types in the object graph that are passed to the method runtime do not match the types that were declared in the class at design-time. You can declare types either implicitly, via the type definition of the field or property, or explicitly through attaching a serialization attribute. Type declarations in the object graph It is important to note here that relying on inheritance is not sufficient. Developers must declare derived types to the XmlSerializer, either by attaching XmlInclude attributes to the base class or by attaching XmlElement attributes to the fields that can hold objects of types derived from the declared type. Take a look at this class hierarchy for an example. Container obj = new Container(); obj.MyField = new Derived(); // legal assignment in the //.NET type system //.

XmlSerializer serializer = new XmlSerializer( typeof( Container ) ); serializer.Serialize( writer, obj ); // Kaboom! You would get an exception from the Serialize() method because there was no explicit type declaration for the XmlSerializer. Exceptions from the XmlSerializer Diagnosing the source of these problems can be tricky at first, because the exceptions from the XmlSerializer do not seem to provide a lot of information about the cause of their occurance; at least, they do not provide the information in a spot where developers typically would look. In most cases, Serialize, Deserialize and even the XmlSerializer constructor throw a rather generic when an error occurs. This exception type can occur in many places in the.NET Framework; it is not specific to the XmlSerializer at all.

To make matters worse, the exception's Message property only yields very generic information, as well. In the example above, the Serialize() method would throw an exception with the following message. There was an error generating the XML document. This message is annoying at best, because you already figured that much when you saw that the XmlSerializer threw an exception. Now you have to find that the exception's Message doesn't help you troubleshoot the problem.

The odd exception message and the non-descriptive exception type reflect the inner workings of the XmlSerializer I introduced earlier in this article. The Serialize() method catches all exceptions thrown in the serialization classes, wraps them in an InvalidOperationException, and throws that up the strack. Reading the Exception Message The trick to get to the 'real' exception information is to examine the exception's InnerException property. The InnerException references the actual exception thrown from within the serialization classes.

It contains very detailed information about the problem and where it occurred. The Exception you would catch running the example above would contain an InnerException with this Message. There is an error in XML document (, ). Whenever a problem occurs. This exception typically contains the real exception in the InnerException property. The type of the InnerException varies according to the actual error that occurred while reading the XML document. If the serializer cannot match up the root element of the document with the type passed to the constructor, a type specified via an XmlInclude attribute, or a type that was specified in the Type[] passed to one of the more sophisticated overloads of the XmlSerializer constructor, then the InnerException is an InvalidCastException.

Keep in mind that the XmlSerializer is looking at the Qname, i.e. The name of the element and the namespace to determine the class into which to deserialize the document. Both have to match the declaration in the.NET class for the XmlSerializer to properly identify the type that is corresponding to the root element of the document. Let's look at an example. Was not expected.

The message is still somewhat ambiguous, but it does point you to the element that is causing the problem. You can go back and closely examine the MyClass class and compare the element name and the XML namespace to the XML serialization attributes in the.NET class. Deserializing Invalid XML Another frequently reported problem is the failure to deserialize invalid XML documents. The XML specification forbids the use of certain in an XML document.

Nevertheless, sometimes you receive XML documents containing these characters anyway. The problem manifests itself in a—you guessed it— InvalidOperationException. In this particular case, though, the InnerException is of type XmlException. The InnerException's message is to the point. Hexadecimal value, is an invalid character You can avoid this problem if you deserialize with an XmlTextReader that has its property set to false. Unfortunately, the XmlTextReader used under the covers by ASP.NET Web services has its Normalization property set to true; i.e., it will not deserialize SOAP messages containing these invalid characters.

Exceptions from the Constructor The last class of problems this article discusses occurs when the constructor of the XmlSerializer reflects over the passed in type. Remember, the constructor recursively examines each public field and property in the type hierarchy to create classes that handle serialization and deserialization. It then compiles the classes on the fly and loads the resulting assembly. There are quite a number of different problems that can occur during this complicated process: • Declared types for the root, or types references by a property or a field, don't provide a default constructor. • A type in the hierarchy implements the collection interface. • Executing a constructor or a property accessor of a type in the object graph requires elevated security privileges. • The code for the generated serialization classes does not compile.

Trying to pass a non-serializable type to the XmlSerializer constructor also results in an InvalidOperationException, but this time the exception does not wrap another exception. The Message property contains a good explanation about why the constructor rejected the passed in Type. Trying to serialize an instance of a class that does not implement a constructor without parameters (default constructor) results in an exception with the Message. File or assembly name abcdef.dll, or one of its dependencies, was not found. File name: 'abcdef.dll' at System.Reflection.Assembly.nLoad(.

) at System.Reflection.Assembly.InternalLoad(. ) at System.Reflection.Assembly.Load(.) at System. Tetriscpl Download Movies. CodeDom.Compiler.CompilerResults.get_CompiledAssembly().

You may wonder what a file not found exception has to do with instantiating a serializer object, but remember: the constructor writes C# files and tries to compile them. The call stack of this exception provides some good information to support that suspicion.

The exception occurred while the XmlSerializer attempted to load an assembly generated by CodeDOM calling the System.Reflection.Assembly.Load method. The exception does not provide an explanation as to why the assembly that the XmlSerializer was supposed to create was not present. In general, the assembly is not present because the compilation failed, which may happen because, under rare circumstances, the serialization attributes produce code that the C# compiler fails to compile. Note This error also occurs when the XmlSerializer runs under an account or a security environment that is not able to access the temp directory. The actual compilation errors are not part of any exception error message thrown by the XmlSerializer, not even an InnerException. This made it very difficult to troubleshoot these exceptions until published his tool. The XmlSerializerPreCompiler The XmlSerializer PreCompiler is a command-line program that performs the same steps as the constructor of the XmlSerializer.

It reflects over a type, generates serialization classes, and compiles them—and because it was purely designed to be a troubleshooting tool, it's safe for the tool to write any compilation errors to the console. The tool is very easy to use. You simply point the tool at the assembly that contains the type that causes the exception, and specify which type to pre-compile. Let's look at an example. One problem that's reported regularly occurs when you attach an XmlElement or and XmlArrayItem attribute to a field that's defined as a jagged array, as in the example below. XmlSerializer-produced source: C: DOCUME~1 LOCALS~1 Temp.cs Now the XmlSerializerPreCompiler gave us the compilation errors and the location of the source file with the code that does not compile.

Debugging Serialization Code Under normal circumstances, the XmlSerializer deletes the C# source files for the serialization classes when they are no longer needed. There is an undocumented, however, which will instruct the XmlSerializer deletes to leave these files on your disk. You can set the switch in your application's.config file. With this switch present in the.config file, the C# source files stay in your temp directory. If you are working on a computer running Windows 2000 or later, the default location for the temp directory is Documents and Settings LocalSettings Temp or Temp, for web applications running under the ASPNET account. The C# files are easy to miss because they have very odd looking, randomly generated filenames, something like: bdz6lq-t.0.cs.

The XmlSerializerPreCompiler sets this diagnostics switch, so you can open the files to inspect the lines on which the XmlSerializerPreCompiler reported compilation errors in Notepad or Visual Studio. You can even step through those temporary serialization classes, because the diagnostics switch also leaves.pdb files with the debugging symbols on your disk. If you need to set a breakpoint in a serialization class, then you can run your application under the Visual Studio debugger.

Once you see messages in the output window that your application loaded, assemblies with these odd looking names from the temp directory, then open the C# files with the corresponding name and set breakpoints just like you can in your own code. Compiliation error output from the diagnostics switch Once you set your breakpoint in a serialization class, you need to execute code that calls the Serialize() or the Deserialize() method on an XmlSerializer object. Note You can only debug serialization and deserialization, but not the code generation process that runs in the constructor. Stepping through the serialization class, you are able to pinpoint every serialization problem. You can use that trick if you want to single-step the deserialization of a SOAP message, since ASP.NET Web services and Web service proxies are built on top of the XmlSerializer. Simply add the diagnostics switch to your config file and set a breakpoint in the class that deserializes the message. I use that technique once in a while, to figure out the correct set of serialization attributes if the WSDL didn't accurately reflect message format when the proxy class was generated.

Conclusion These tips should help you diagnose serialization problems with the XmlSerializer. Most problems you encounter stem either from bad combinations of the XML serialization attributes or from XML that doesn't match the type being deserialized.

The serialization attributes control the generation of the code for the serialization classes, and can lead to compilation errors or runtime exceptions. Inspecting the exceptions thrown by the XmlSerializer closely will help you identifying the source of runtime exceptions. If you need to dig deeper to diagnose a problem, then XmlSerializerPreCompiler tool assists you in finding compilation errors. If neither approach leads you to the root cause of the problem, you can inspect the code for the automatically created serialization classes and step through them in the debugger. Acknowledgements I would like to thank and for their feedback and editorial suggestions with this article.