I want to create a dynamic object from a string of XML. Is there an easy way of doing this?
Example String.
<test><someElement><rep1>a</rep1><rep1>b</rep1></someElement></test>
I'm trying to create an mvc editor for passing data through nvelocity and would like people on the front end to input xml as there data for parsing.
Thanks in advance.
You need 2 things to achieve this :
1) Valid xml
2) C# class which has same data members as in your input xml.
You need to create one object of C# class then enumerate through all the elements of xml and when by using switch for each of the element name, you can take inner text property of that element and assign it to respective data member of object.
C# code might look like following (you need to fill in the gaps):
class test {
List<string> someElement;
}
class xmlEnum
{
static test createObject(string inputXml)
{
test t = new test();
// load input xml in XmlDocument class
// and start iterating thorugh all the elements
swithc(elementName)
{
case rep1:
t.someElement.add(element.innerText);
break;
// some more cases will go here
}
// finally return the object;
return t;
}
}
I hope this will help you.
I don't think there's a ready-made dynamic solution to this. If I understand your question correctly, you would like to do something like this.
SomeDynamicXmlObject test = new SomeDynamicXmlObject(yourteststring);
var rep1 = test.SomeElement.rep1;
The closest I can think of you could get to that, is to use XElement classes, something like this:
XElement test = XElement.Parse(yourteststring);
var rep1 = test.Element("SomeElement").Element("rep1");
If that's not good enough, I'm afraid you will have to write something yourself that will parse the xml and create the object on the fly. If you know in advance what the xml will look like, you could use shekhars code, but I guess from your comments that you don't.
If you have schema for xml available and if this is needed in dev/build environment then a round about way to do this will be
Use XSD tool to parse schema and generate code from it
Build the generated code using command line complier or compiler services to generate assmebly. Now you have a type available there that can be used.
Needless to say this will be a quite slow and out-of-proc tools will be used here.
Another (not an easy way but faster) way that would not have dev env dependencies would be to parse your xml and generate dynamic type using reflection. See this article to check how to use Reflection.Emit
Related
I have a bit of a weird issue. Working in C# script with SSIS I have developed a need to build a List based off Dynamic Data.
Background
To explain it, a script task is fired that has a variable API URL, this goes off and pulls a JSON string back and then throws it into a strongly typed list using the following code.
var listobject = get_APIData<ApplicationOneDataSet>(url)
The class that does this is long winded and not really needed in the context of this issue.
ApplicationOneDataSet is a strongly typed match to one of the possible JSON results returned by get_APIData.
Now I have a need to change ApplicationOneDataSet to ApplicationTwoDataSet dynamically based on which API URL I pass to the script.
So what I have done is send through a second variable to the script called class name which contains the string "ApplicationDataSetOne" or "ApplicationDataSetTwo" based on which context I call it under.
The Question
My question is how can I dynamically vary this line:
var listobject = get_APIData<ApplicationOneDataSet>(url)
With the string variable passed into the script.
My original thinking was something along the lines of this:
var ClassType = (string) Dts.Variables["AppClassName"].Value;
Type type = Type.GetType(ClassType);
var listobject = get_APIData<type>(url)
Though it doesn't seem to like that. Any tips would be great!
As long as there is exactly two types you can use and you know them at compile time, I would not look further than a simple if. It works, it's easy, everyone understands it.
You can do it totally dynamic at runtime, but that's a huge pain in the... where you don't want it to be. If you really want to go down that rabbit hole, you can find more information here.
I'm not sure I fully understood what you are trying to do, but how about writing an interface ApplicationDataSet and then making a list of it? This way your list is going to be able to contain both types of data.
I need to serialize the strings from a resource file (.resx) into a JSON object. The resource file's keys are in flux and thus I cannot just create a C# object that accepts the appropriate values. It needs to be a dynamic solution. I am able to loop through the key-value pairs for the file, but I need an easy way to serialize them to JSON.
I know I could do:
Object thing = new {stringOne = StringResource.stringOne; ...}
But, I'd rather have something like:
Object generic = {}
foreach (DictionaryEntry entry in StringResource) {
generic.(entry.Key) = entry.Value
}
Or should I just create a custom JSON serializer that constructs the object piecemeal (i.e. foreach loop that appends part of the JSON string with each cycle)?
EDIT
I ended up writing a quick JSON serializer that constructs the string one field at a time. I didn't want to include a whole JSON library as this is the only use of JSON objects (for now at least). Ultimately, what I wanted is probably impractical and doesn't exist as it's function is better served by other data structures. Thanks for all the answers though!
If you're using C# 4.0, you should look at the magical System.Dynamic.ExpandoObject. It's an object that allows you to dynamically add and remove properties at runtime, using the new DLR in .NET 4.0. Here is a good example use for the ExpandoObject.
Once you have your fully populated ExpandoObject, you can probably easily serialize that with any of the JSON libraries mentioned by the other excellent answers.
This sounds like an accident waiting to happen (i.e. creating output prior to cementing the structure), but it happens.
The custom JSON serializer is a compelling option, as it allows you to easily move from your dictionary into a JSON format. I would look at open source libraries (JSON.NET, etc) to see if you can reduce the development time.
I also think setting up in a slightly more structured format, like XML, is a decent choice. It is quite easy to serialize from XML to JSON using existing libraries, so you avoid heavy customization/
The bigger question is what purposes will the data ultimately serve. If you solve this problem using either of these methods, are you creating bigger problems in the future.
Probably I would use JSON.NET and the ability to create JSON from XML.
Then, you could create an XML in-memory and let JSON.NET convert it to JSON for you. Maybe if you dig deeper into the API, there are other options, too.
Newtonsoft is a library that has all kinds of nifty JSON tools...among them, on-the-fly one-line serializer and deserializers...check it out, it's my favorite JSON library out there
http://james.newtonking.com/pages/json-net.aspx
If I remember correctly, it has a class that will convert JSON to a .NET object without having to create the .NET object first. Think it is in the Json.Convert class
The way I do it is:
var serialiser = new System.Web.Script.Serialization.JavaScriptSerializer();
string json = serialiser.Serialize(data);
context.Response.Write(json);
Hi is it possible to Create New Classes in C# ,classes which the Application Read's from XML and Declare they're Attributes also reading from XML .
like :
<item id=1>
<Name>John</Name>
<Surname>Kennedy</Surname>
<Age>24</Age>
</item>
bests.
Yes it is with System.Reflection.Emit namespace.
But in .net 4.0 you can use dynamic keywoard for this. Like this http://blogs.msdn.com/b/mcsuksoldev/archive/2010/02/04/dynamic-xml-reader-with-c-and-net-4-0.aspx
without dynamic, even if you create new class, you will need reflection to access their properties
Yes it is.
Here you can find how to.
But instead of this you can also store this structure in a Map, where the key is and id and value is a other map that store the properties where key is the name and values is the value.
You can deserialize this XML in a new class! Try something like this:
public static T DeserializeObject<T>(string filePath)
{
XmlDocument doc = new XmlDocument();
doc.Load(filePath);
XmlNodeReader reader = new XmlNodeReader(doc.DocumentElement);
XmlSerializer ser = new XmlSerializer(typeof(T));
object obj = ser.Deserialize(reader);
return (T)obj;
}
You have to use Reflection api for doing that which is a complicated thing. Please describe your scenario. Maybe there are simpler approaches.
here is a simple introduction for you
http://blog.alxandr.me/2010/10/16/an-introduction-to-system-reflection-emit-and-opcodes/
have fun
I doesn't really make sense to. Since C# is strongly typed, you're not going to know at compile type what the object looks like, so you're not going to be able to use it.
Maybe you're better off making an object that uses a Dictionary with the key being the node name. Then you can query the dictionary to find what properties it has.
I need a sensible way to draw arbitrary text files into a C# program, and produce an arbitrary anonymous type object, or perhaps a composite dictionary of some sort.
I have a representative text file that looks like this:
adapter 1: LPe11002
Factory IEEE: 10000000 C97A83FC
Non-Volatile WWPN: 10000000 C93D6A8A , WWNN: 20000000 C93D6A8A
adapter 2: LPe11002
Factory IEEE: 10000000 C97A83FD
Non-Volatile WWPN: 10000000 C93D6A8B , WWNN: 20000000 C93D6A8B
Is there a way to get this information into an anonymous type object or some similar structure?
The final anonymous type might look something like this, if it were composed in C# by hand:
new
{
adapter1 = new
{
FactoryIEEE = "10000000 C97A83FC",
Non-VolatileWWPN = "10000000 C93D6A8A",
WWNN = "20000000 C93D6A8A"
}
adapter2 = new
{
FactoryIEEE = "10000000 C97A83FD",
Non-VolatileWWPN = "10000000 C93D6A8B",
WWNN = "20000000 C93D6A8B"
}
}
Note that, as the text file's content is arbitrary (i.e. the keys could be anything), a specialized solution (e.g. that looks for names like "FactoryIEEE") won't work. However, the structure of the file will always be the same (i.e. indentation for groups, colons and commas as delimiters, etc).
Or maybe I'm going about this the wrong way, and you have a better idea?
You're going about this the wrong way. Your "anonymous type object" data is hard to construct and hard to use. To construct it, you'd have to use reflection trickery. And for what?
Consider a PrintReport function. This function would not get any simpler because of the ATO usage. Far from it, it'd get more complicated and slow, having to use reflection itself to iterate over the keys. Your solution might have made sense if there was a small, fixed number of possible keys. Then usage syntax such as "obj.FactoryIEEE" might have been preferred.
The way I'd go about this is with a List<Dictionary<string, string>>, or, say a List<AdapterRecord> where AdapterRecord is
class AdapterRecord
{
public string Name { get; set; }
public Dictionary<string, string> Parameters { get; set; }
}
Check out this 2-part article. It parses XML files in a fluent way. It can be adapted to parse your text files I think.
Fluent XML Parsing Using C#'s Dynamic Type Part 1
Fluent XML Parsing Using C#'s Dynamic Type Part 2
It uses C# 4 dynamic typing to do what you want.
It looks like there's no way to do this even in C# 4.
Besides, thinking about it if you don't know what the keys will be then any sort of strongly typed access would be tough, and a simple split + insertion into dictionary/list/etc. would make more sense.
While I don't love them, perhaps a DataTable would serve...
If I am dealing with several standard xml formats what would be the best practice way of encapsulating them in C# 3.5? I'd like to end up with something similar to the System.ServiceModel.Syndication namespace.
A class that encapsulates the ADF 1.0 XML standard would be one example. It has the main XML root node, 6 child elements, 4 of which are required IIRC, several required and optional elements and attributes further down the tree. I'd like the class to create, at a minimum, the XML for all the required pieces all the way up to a full XML representation. (Make sense).
With LINQ 4 XML and extension classes, etc, etc, there has to be some ideas on quickly generating a class structure for use. Yes? No? :)
Am not sure if I gave enough details to get one correct answer but am willing to entertain ideas right now.
TIA
XML serialization seems a good approach. You could even use xsd.exe to generate the classes automatically...
EDIT
Note that the class names generated by the tool are usually not very convenient, so you might want to rename them. You might also want to change arrays of T to List<T>, so that you can easily add items where needed.
Assuming the class for the root element is named ADF, you can load an ADF document as follows :
ADF adf = null;
XmlSerializer xs = new XmlSerializer(typeof(ADF));
using (XmlReader reader = XmlReader.Create(fileName))
{
adf = (ADF)xs.Deserialize(reader);
}
And to save it :
ADF adf = ...; // create or modify your document
...
XmlSerializer xs = new XmlSerializer(typeof(ADF));
using (XmlWriter writer = XmlWriter.Create(fileName))
{
xs.Serialize(writer, adf);
}
Why not just follow the pattern of the SyndicationFeed object in the Syndication namespace? Create a class that takes in a Uri to the xml document or just takes in the document fragment.
Then parse the document based on your standards (this parsing can be done using LinqToXml if you wanted to, though regEx might be faster if you are comfortable with them). Throw exceptions or track errors appropriately when the document doesn't pass the specification rules.
If the document passes the parse step then break the pieces of the document out into public getter properties of your object. Then return the fully hydrated object back to the consumer for use
Seems pretty straight forward to me. Is that what you are after or are you looking for something more than this?