Compile XSD to C# objects include namespace - c#

I'm generating objects and class es from XSD files. But the classes created under one namespace and not with the target namespace of the XSD.
How can I compile the schema, and the class should be generated under the namespace?
Here is my code fore example:
// generate an assembly representing the given schema:
var codeNamespace = new CodeNamespace(namespaceName);
var codeProvider = new CSharpCodeProvider();
var codeGenerationOptions = new CodeGeneratorOptions();
using (var writer = new StringWriter())
{
codeProvider.GenerateCodeFromNamespace(codeNamespace, writer,
codeGenerationOptions);
code = writer.ToString();
}

Your code example works in that it puts the generated code in the namespace you specify in your namespaceName variable. If you want your namespace to match the XSD, you can set your namespaceName variable accordingly.
For example, if I define string namespaceName = "My.Namespace.One"; in your example code, the resulting value of code is "namespace My.Namespace.One {\r\n\r\n}" as expected.
Thus you would simply need to read the namespace from your XSD and assign it to namespaceName If your issue is that you are wanting to use multiple namespaces, then the issue is related to how you process the XSD for code generation, which is not shown at all in your example.
However to actually compile the code you generate, the namespace will need to conform to C# limitations. A namespace like http://schemas.microsoft.com/winfx/2006/xaml would not compile in C#. That namespace may (I'm not sure) be valid at the IL byte code level, but even if it is I would really wonder if what you are doing is worth expending that sort of effort, especially considering it would be a pain for C# to use the generated assembly.
I have the feeling that some details may be missing from your question/example and this may not be the info you are looking for; however, I believe this answer is consistent with what you have provided.

Related

How do I get the primary namespace in an assembly? [duplicate]

Given an instance of System.Reflection.Assembly.
I have come across this dilemma plenty of times when I want to load a resource from the current assembly by its manifest resource stream.
The fact is that if you embed a file as a resource in your assembly using Visual Studio its manifest resource name will be derived from the default namespace of the assembly as defined in the Visual Studio project.
The best solution I've come up with (to avoid hardcoding the default namespace as a string somewhere) is to simply ensure your resource loading code is ALWAYS happening from inside a class that's also in the default namespace and then the following near-generic approach may be used.
This example is loading an embedded schema.
XmlSchema mySchema;
string resourceName = "MyEmbeddedSchema.xsd";
string resourcesFolderName = "Serialisation";
string manifestResourceName = string.Format("{0}.{1}.{2}",
this.GetType().Namespace, resourcesFolderName, resourceName);
using (Stream schemaStream = currentAssembly.GetManifestResourceStream(manifestResourceName))
mySchema = XmlSchema.Read(schemaStream, errorHandler);
See also: How to get Namespace of an Assembly?
Edit: Also noticed a very detailed answer to the question I'm answering at http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/3a469f5d-8f55-4b25-ac25-4778f260bb7e
Another edit in case people with same question come looking: Excellent idea to solve the resource-loading question here: How get the default namespace of project csproj (VS 2008)
Not possible. Nothing specifies a "Root" namespace. The default namespace in the options is a visual studio thing, not a .net thing
There could be any number of namespaces in a given assembly, and nothing requires them to all start from a common root. The best you could do would be to reflect over all the types in an assembly and build up a list of unique namespaces contained therein.
I just created an empty internal class called Root and put it in the project root (assuming this is your root namespace). Then I use this everywhere I need the root namespace:
typeof(Root).Namespace;
Sure I end up with an unused file, but it's clean.
Assemblies don't necessarily have a root namespace. Namespaces and Assemblies are orthogonal.
What you may be looking for instead, is to find a type within that Assembly, and then find out what its namespace is.
You should be able to accomplish this by using the GetExportedTypes() member and then using the Namespace property from one of the returned Type handles.
Again though, no guarantees all the types are in the same namespace (or even in the same namespace hierarchy).
I use typeof(App).Namespace in my WPF application.
App class is mandatory for any WPF application and it's located in root.
Get Types gives you a list of Type objects defined in the assembly. That object has a namespace property. Remember that an assembly can have multiple namespaces.
GetType(frm).Namespace
frm is the startup Form
Namespaces have nothing to do with assemblies - any mapping between a namespace and the classes in an assembly is purely due to a naming convention (or coincidence).
There actually is an indirect way to get it, by enumerating the names of the assembly's manifest resources. The name you want ends with the part of it that you know.
Rather than repeat the code here, please see get Default namespace name for Assembly.GetManifestResourceStream() method
The question I had that landed me here was, "If I call library code N methods deep and want the namespace of the Project - for example the MVC app that's actually running - how do I get that?"
A little hacky but you can just grab a stacktrace and filter:
public static string GetRootNamespace()
{
StackTrace stackTrace = new StackTrace();
StackFrame[] stackFrames = stackTrace.GetFrames();
string ns = null;
foreach(var frame in stackFrames)
{
string _ns = frame.GetMethod().DeclaringType.Namespace;
int indexPeriod = _ns.IndexOf('.');
string rootNs = _ns;
if (indexPeriod > 0)
rootNs = _ns.Substring(0, indexPeriod);
if (rootNs == "System")
break;
ns = _ns;
}
return ns;
}
All this is doing is getting the stacktrace, running down the methods from most recently called to root, and filtering for System. Once it finds a System call it knows it's gone too far, and returns you the namespace immediately above it. Whether you're running a Unit Test, an MVC App, or a Service, the System container is going to be sitting 1 level deeper than the root namespace of your Project, so voila.
In some scenarios where System code is an intermediary (like System.Task) along the trace this is going to return the wrong answer. My goal was to take for example some startup code and let it easily find a class or Controller or whatever in the root Namespace, even if the code doing the work sits out in a library. This accomplishes that task.
I'm sure that can be improved - I'm sure this hacky way of doing things can be improved in many ways, and improvements are welcome.
Adding to all the other answers here, hopefully without repeating information, here is how I solved this using Linq. My situation is similar to Lisa's answer.
My solution comes with the following caveats:
You're using Visual Studio and have a Root Namespace defined for your project, which I assume is what you're asking for since you use the term "root namespace"
You're not embedding interop types from referenced assemblies
Dim baseNamespace = String.Join("."c,
Me.GetType().Assembly.ManifestModule.GetTypes().
Select(Function(type As Type)
Return type.Namespace.Split("."c)
End Function
).
Aggregate(Function(seed As String(), splitNamespace As String())
Return seed.Intersect(splitNamespace).ToArray()
End Function
)
)
Here as a rather simple way to get the root namespace for a website project.
''' <summary>
''' Returns the namespace of the currently running website
''' </summary>
Public Function GetWebsiteRootNamespace() As String
For Each Asm In AppDomain.CurrentDomain.GetAssemblies()
If Asm Is Nothing OrElse Asm.IsDynamic Then Continue For
For Each Typ In Asm.GetTypes
If Typ Is Nothing OrElse Typ.Name Is Nothing Then Continue For
If Typ.Name = "MyProject" Then Return Typ.Namespace.Split("."c)(0)
Next
Next
Return Nothing
End Function
This simply checks all the loaded assemblies for the "MyProject" type and returns the root namespace for that type. This is useful for logging when you have multiple web projects in a single solution sharing a log system. Hope this helps someone.
This solution works if you are trying to load an embedded resource.
var assembly = System.Reflection.Assembly.GetExecutingAssembly();
string[] resourceNames = assembly.GetManifestResourceNames();
string resourceNameNoNamespace = $"Languages.{languageSupport.IsoCode}.Languages.xml";
var match = resourceNames.SingleOrDefault(rn => rn.EndsWith(resourceNameNoNamespace));
Dim applicationNamespace = TextBeforeFirst(Assembly.GetCallingAssembly().EntryPoint.DeclaringType.Namespace, ".")
Public Function TextBeforeFirst(value As String, expression As String) As String
If String.IsNullOrEmpty(value) Or String.IsNullOrEmpty(expression) Then Return Nothing
Dim index = value.IndexOf(expression)
If index = -1 Then Return Nothing
Dim length = index
Return value.Substring(0, length)
End Function

DataContractSerializer namespace for derived class does not match specified in attribute

I'm expecting XML output as follows:
<MyBase type="MyDerived"
xmlns="http://www.mynamespace.com/MySchema" />
Instead, my actual output is as follows:
<MyBase i:type="MyDerived"
xmlns="http://www.mynamespace.com/MySchema"
xmlns:i="http://www.w3.org/2001/XMLSchema-instance" />
I'm using the following class definitions to attempt to generate my expected output:
MyBase.cs
namespace MyProject
{
[KnownType(typeof(MyDerived))]
[DataContract(Namespace = MyBase.Namespace)]
public abstract class MyBase
{
public const string Namespace = "http://www.mynamespace.com/MySchema";
}
}
MyDerived.cs
namespace MyProject.Events
{
[DataContract(Namespace = MyBase.Namespace)]
public sealed class MyDerived : MyBase {}
}
And I'm using the following serialization code:
var knownTypes = new Type[]
{
typeof(MyDerived)
};
var xmlDictionary = new XmlDictionary(1);
var settings = new DataContractSerializerSettings();
settings.KnownTypes = knownTypes;
settings.RootNamespace = xmlDictionary.Add(MyBase.Namespace);
serializer = new DataContractSerializer(typeof(MyBase), settings);
var actual = String.Empty;
using (var memoryStream = new MemoryStream())
{
serializer.WriteObject(memoryStream, new MyDerived());
memoryStream.Position = 0;
using (var streamReader = new StreamReader(memoryStream))
{
actual = streamReader.ReadToEnd();
}
}
I'm not sure why it's using the XMLSchema-instance namespace for my derived object instead of the namespace I've specified to use. I've spent over an hour digging around StackOverflow, Google, and MSDN trying to figure out what I'm doing wrong, but I must be missing it. It seems so close, it must be a simple mistake.
Is this a problem with my class structure, or am I misapplying attributes in some way?
How can I get my expected output?
You may just be misreading the XML and things are working as desired. In your XML, the namespace xmlns:i="http://www.w3.org/2001/XMLSchema-instance" is only being used to qualify the attribute i:type, and nothing else. All of your actual data is in the namespace you specify. If the object itself were in a different namespace, you would see something like:
i:type="i:MyDerived"
But you're not.
http://www.w3.org/2001/XMLSchema-instance is a W3C globally standard namespace, knowledge of which is built in to DataContractSerializer (as well as many other XML serializers). It contains 4 built-in attributes defined as follows in the standards document:
nil: Signals that an element may be ·valid· without content if it has this attribute with the value true.
schemaLocation and noNamespaceSchemaLocation: used to provide hints as to the physical location of schema documents.
type: An element information item in an instance may explicitly assert its type using the attribute type. The value of this attribute is a ·QName·.
The i:type you are seeing is the last of these standard, globally recognized attributes. It says: "this element has the following type". Reasons for DataContractSerializer to use it to represent .Net type information could include:
It is standard. For instance XmlSerializer recognizes and supports the same attribute.
Your element might have its own data attribute named type. If so, it would reside in its own namespace, not http://www.w3.org/2001/XMLSchema-instance. The latter is reserved by convention for schema information not content, thereby avoiding name collision.
For more, see Understanding Known Types and Data Contract Known Types.
Unfortunately you'll not be able to achieve it even using custom XmlWriter. DataContractSerializer doesn't work like XMLSerializer. The information into your xml is added to support the fact:
The line xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" tells the XML parser that this document should be validated against a schema.
Also these namespaces are considered as reserved namespaces. So if you try to override them .Net runtime will throw exception.
#dbc explained it very well and inclusion of the namespaces is part of a pretty standard process and is harmless for your xml.
If you really need to get rid of this default namespace then you just have to hack your XML output with string replace method. But this may lead you to problems while desalinizing.

Error "CS0104: 'DataType' is an ambiguous reference between 'System.ComponentModel.DataAnnotations.DataType' and 'CarlosAg.ExcelXmlWriter.DataType"

I am getting this error:
"CS0104: 'DataType' is an ambiguous reference between
'System.ComponentModel.DataAnnotations.DataType' and
'CarlosAg.ExcelXmlWriter.DataType'"
while running an ASP.NET 4.0 application. Can any one help me on this issue?
As described in the documentation on Compiler Error CS0104 you've got a symbol clash - there are two classes in scope of your source file which are both called DataType - one is in the namespace System.ComponentModel.DataAnnotations and the other is in the namespace CarlosAg.ExcelXmlWriter.DataType'.
You need to do one of the following to resolve this:
1. Explicitly provide the full namespace prefix on each usage, i.e.
System.ComponentModel.DataAnnotations.DataType and CarlosAg.ExcelXmlWriter.DataType:
var cdt = new CarlosAg.ExcelXmlWriter.DataType();
var sdt = new System.ComponentModel.DataAnnotations.DataType();
OR 2. Or use a using directive to alias the namespaces / types, e.g.
using SystemDT = System.ComponentModel.DataAnnotations;
using Carlos = CarlosAg.ExcelXmlWriter;
And then then identify the types with the namespace aliases, e.g..
var dt = new Carlos.DataType();
OR 3. You can also alias at the class level:
using SystemDataType = System.ComponentModel.DataAnnotations.DataType;
using CarlosDataType = CarlosAg.ExcelXmlWriter.DataType;
...
var myObj = new CarlosDataType();
OR 4. If you don't need to symbols from both namespaces, then delete the unused namespace from the using clause.
My preference would be for Option 2 - it makes it clearer to the reader that there is a namespace clash, without being too verbose (like Option 1 is)
Edit
Re: "I tried by giving full prefix but still I am getting error "CS0138: A
using namespace directive can only be applied to namespaces;
'CarlosAg.ExcelXmlWriter.DataType' is a type not a namespace"
(All relating to point #2, above). The error message refers to a situation like this, which isn't permitted in .Net (but is permitted in Java imports)
// i.e. This won't work, can't import at a class level unless it is aliased
using System.ComponentModel.DataAnnotations.DataType;
As per my answer, I would recommend that you alias the namespace, and then use the alias prefix to disambiguate between the 2 DataTypes
I had the same problem. The solution I used was to delete all using and make the references again. Worked perfectly.

"Namespace prefix not defined" when it actually is defined

I'm having trouble deserializing XML with an "undefined" namespace prefix which really is defined.
We've published an internal web service in C# which serves a variety of clients. A new client's IDE insists on declaring xsi:type for every element in its XML output, and they can't turn off this "feature".
The XML message they produce goes like this, where "namespace" is the correct namespace.
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<myOperation xsi:type="ns1:namespace" xmlns="namespace" xmlns:ns1="namespace">
<inputString xsi:type="xsd:string">ABCDEF</inputString>
<books xsi:type="ns1:booksType">
<bookID xsi:type="xsd:string">ABC123</bookID>
<bookID xsi:type="xsd:string">DEF456</bookID>
</books>
<!-- ... snip... -->
</myOperation>
</soapenv:Body>
<books> is basically an array of strings.
The service method accepts as XmlNode, but XmlSerializer throws a "prefix 'ns1' not defined" error. (It is defined in a parent node, but apparently that is not good enough.) I have a similar problem using wsdl.exe to generate classes and deserialize the input for me.
Using XmlNamespaceManager to specify prefixes doesn't seem right -- akin to magic numbers, and I can't predict which prefix a given consumer will declare anyway. Is there a way to handle this without stripping the attributes out (books.Attributes.RemoveAll)? That doesn't feel particularly elegant either.
I've found that books.OuterXML does not contain any information for 'ns1' unless I hack the element inbound to use that prefix (), so I can see why it complains, but I don't yet understand why 'ns1' isn't recognized from its previous definition above.
Many thanks for any help, or at least education, someone can provide.
Edits: it works fine if I change <books> to use the prefix, i.e. <ns1:books xsi:type="ns1:booksType">. This works whether I've defined xmlns or no. That may be consistent with this answer, but I still don't see how I would feasibly declare the prefix in the service code.
#Chris, certainly. Hope I can strike a balance between "stingy with closed source" and "usable for those who would help". Here "books" is the XmlNode received in the service method parameter. (Not to get off topic, but will also humbly take suggestions to improve it in general; I'm still a novice.)
XmlSerializer xmlSerializer = new XmlSerializer(typeof(booksType));
StringReader xmlDataReader = new StringReader(books.OuterXml);
books = (booksType)xmlSerializer.Deserialize(xmlDataReader);
The class is pretty much this:
[Serializable()]
[XmlRoot("books", Namespace = "namespace")]
[XmlTypeAttribute(TypeName = "booksType", Namespace = "namespace")]
public class booksType
{
[XmlElement(ElementName = "bookID")]
public string[] bookIDs { get; set; }
}
Your deserialization code could look something like this:
XmlSerializer sz = new XmlSerializer(typeof(booksType));
var reader = new XmlNodeReader(booksXmlNode);
var books = sz.Deserialize(reader);
[EDIT] This is better, because the namespace declarations are preserved with the XmlNode, whereas converting to an XML string via OuterXml appears to slice off the namespace declaration for the ns1 prefix, and the serializer then barfs on the type attribute value containing this prefix. I imagine this is a bug in the XML implementation but maybe an XML guru can confirm this.
This should get you past the error you are seeing, but whether it solves the problem completely I'm not sure.
[FURTHER EDIT] As noted in the comments below, there is a bug in the .NET XmlSerializer which is causing the deserialization to fail. Stepping through the deserialization code in the generated assembly, there is a point where the following condition is tested:
(object) ((System.Xml.XmlQualifiedName)xsiType).Namespace == (object)id2_namespace))
Although the Namespace property of the XmlQualifiedName has the same value ('namespace') as the string variable id2_namespace, the condition is evaluating to false because it is coded as an object identity test rather than a test for string value equivalence. Failing this condition leads directly to the exception reported by OP.
As far as I can see, this bug will always cause deserialization to fail whenever the XML for the object being deserialized uses one prefix on the object's root element name, and another prefix (defined as the same namespace) on that element's xsi:type attribute.

Can I hide classes in the global namespace in C#?

In a visual studio 2008 solution, I have two versions of the same class in two different namespaces.
In VB, if I do this:
imports MyNamespace
' ...
dim x as DuplicatedClass = new DuplicatedClass()
it uses MyNamespace.DuplicatedClass instead of the globally-namespaced DuplicatedClass. Meanwhile, in C#, doing this:
using MyNamespace;
// ...
DuplicatedClass x = new DuplicatedClass();
uses the globally-namespaced DuplicatedClass. To use the other version, I have to use MyNamespace.DuplicatedClass.
I realize this is a problematic setup, but I can't change it. Is there a way to prevent C# from seeing the globally namespaced class, or to specifically un-load it, or...? Given how many classes are in the global namespace, being forced to choose the namespace every time could get pretty time-costly.
Perhaps the best you could do is create a using alias:
//create alias
using defDuplicatedClass = MyNamespace.DuplicatedClass;
defDuplicatedClass x = new defDuplicatedClass();
The alias is file scoped. So you'd have to repeat it at the top of each file as needed, but perhaps that is better than repeating a namespace with every occurance of DuplicatedClass.

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