How to convert database table into XML in ASP.NET MVC4 - asp.net

Question

I am trying to convert SQL server database table into XML file. I followed this solution.
I have created this class as shown in solution
public class XmlResult : ActionResult
{
private object objectToSerialize;
/// <summary>
/// Initializes a new instance of the <see cref="XmlResult"/> class.
/// </summary>
/// <param name="objectToSerialize">The object to serialize to XML.</param>
public XmlResult(object objectToSerialize)
{
this.objectToSerialize = objectToSerialize;
}
/// <summary>
/// Gets the object to be serialized to XML.
/// </summary>
public object ObjectToSerialize
{
get { return this.objectToSerialize; }
}
/// <summary>
/// Serialises the object that was passed into the constructor to XML and writes the corresponding XML to the result stream.
/// </summary>
/// <param name="context">The controller context for the current request.</param>
public override void ExecuteResult(ControllerContext context)
{
if (this.objectToSerialize != null)
{
context.HttpContext.Response.Clear();
XmlRootAttribute root = new XmlRootAttribute("response");
var xs = new System.Xml.Serialization.XmlSerializer(this.objectToSerialize.GetType(), root);
context.HttpContext.Response.ContentType = "text/xml";
xs.Serialize(context.HttpContext.Response.Output, this.objectToSerialize);
}
}
Instead of this:
public ActionResult GetStuffAsXml(int id)
{
var dbStuff = db.GetStuff(id);
// fetch stuff in database
return new XmlResult(dbStuff);
}
I have written this(my purpose is to get all products):
public ActionResult Transfer()
{
var product = from s in db.Product
select s;
// fetch stuff in database
return new XmlResult(product);
}
In debugging process, this error came out:
To be XML serializable, types which inherit from IEnumerable must have
an implementation of Add(System.Object) at all levels of their
inheritance hierarchy.
System.Data.Entity.Infrastructure.DbQuery`1[[Overstock.Models.Product,
Overstock, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]
does not implement Add(System.Object).
Source error:
Line 42: var xs = new
System.Xml.Serialization.XmlSerializer(this.objectToSerialize.GetType(),
root);
I assume that error is coming out because I am taking products in wrong way:
var product = from s in db.Product select s;
In what form I should send data to XmlResult class in order to convert SQL Server table to XML file format?

Answer 1

If 'db' is a DbContext in this method
var product = from s in db.Product
select s;
// fetch stuff in database
return new XmlResult(product);
Then you are not getting out a DataRow or DataTable, you're getting a collection of strongly typed classes. If you want make xml from them use this code:
public static string SerializeAsXml<T>(T element)
{
XmlSerializer xmlSerializer = new XmlSerializer(element.);
StringWriter textWriter = new StringWriter();
xmlSerializer.Serialize(textWriter, element.GetType());
return textWriter.ToString();
}
call it
var products = from s in db.Product
select s;
// fetch stuff in database
return SerializeAsXml(products);