There was an error while trying to serialize parameter http://tempuri.org/:obj. The InnerException message was ‘Type ‘System.Collections.Generic.List`1[Employee, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]’ with data contract name ‘ArrayOfEmployee:http://schemas.datacontract.org/2004/07/Interfaces’ is not expected. Add any types not known statically to the list of known types – for example, by using the KnownTypeAttribute attribute or by adding them to the list of known types passed to DataContractSerializer.
Hi if you are getting your hands dirty with WCF and got your mind blown up with the error as shown above or shown in Screen i have medicine of it..so go ahead!!!!
I am creating one simple serviceoperation which should take argument as an object but i will pass instance of my generic list which can be like List<Employee> or List<Person> and all this….because in service implementation i will do further operation based on type….I have created one application like this:
IService.cs
Service.CS
Employee.CS
Client.CS
Now when i run this application it gives me error of KnownTypeAttribute and serialization
Cause:
Actually root cause of problem is that we have defined object as our datacontract but when we pass List<Employee> or List<Person> it dosen’t knows what to serialize and send from wire…..hoohh…….simple if i have told you to say HI and it i will sat Bye…you can’t understand what i mean to say…so i need to help you in understanding Bye…Simple!!!!!so let us tell CLR that hey what to do if i pass List<Employee> or any type which i want to pass..
Solution:
Open your service contract IService.cs
and after [ServiceContract] Add [ServiceKnownType(typeof(List<Employee>))] or [ServiceKnownType(typeof(List<Person>))]….and Run the application…modified IService.cs looks like this:
Hope it helped you…Wants to say..Thanks say it to
Sowmy Srinivasan’s for nice and in-depth article:http://blogs.msdn.com/sowmy/
Question:
I am just wondering suppose if i have 50 Types which i want to pass then i need to declare all this on top of IService….just searching some alternative for it..if i found will let you know and hoping for the same….
A Place for C Sharpers/.Netters 
I tried this, but didn’t work
also tried this
http://silverlight.net/forums/p/21513/77019.aspx#77019
no luck
finally i am taking top 100 records.
hi, for me this code don’t work
ERROR:
System.Runtime.Serialization.SerializationException: Type ‘System.Collections.Generic.List`1[[ClientWS.wcfServerService.Employee, ClientWS, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]’ with data contract name ‘ArrayOfEmployee:http://schemas.datacontract.org/2004/07/wcfServer‘ is not expected. Add any types not known statically to the list of known types – for example, by using the KnownTypeAttribute attribute or by adding them to the list of known types passed to DataContractSerializer.
at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeAndVerifyType(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, Boolean verifyKnownType, RuntimeTypeHandle declaredTypeHandle)
at System.Runtime.Serialization.XmlObjectSerializerWriteContext.SerializeWithXsiTypeAtTopLevel(DataContract dataContract, XmlWriterDelegator xmlWriter, Object obj, RuntimeTypeHandle originalDeclaredTypeHandle)
at System.Runtime.Serialization.DataContractSerializer.InternalWriteObjectContent(XmlWriterDelegator writer, Object graph)
at System.Runtime.Serialization.DataContractSerializer.InternalWriteObject(XmlWriterDelegator writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObjectHandleExceptions(XmlWriterDelegator writer, Object graph)
at System.Runtime.Serialization.XmlObjectSerializer.WriteObject(XmlDictionaryWriter writer, Object graph)
at System.ServiceModel.Dispatcher.DataContractSerializerOperationFormatter.SerializeParameterPart(XmlDictionaryWriter writer, PartInfo part, Object graph)
My code:
Server side – WCF
IService1.cs
namespace wcfServer
{
// NOTE: If you change the interface name "IService1" here, you must also update the reference to "IService1" in Web.config.
[ServiceContract]
[ServiceKnownType(typeof(List))]
public interface IService1
{
[OperationContract]
string ParseObject(object obj);
}
}
Service1.svc.cs
namespace wcfServer
{
// NOTE: If you change the class name "Service1" here, you must also update the reference to "Service1" in Web.config and in the associated .svc file.
public class Service1 : IService1
{
#region Implementation of IService1
public string ParseObject(object obj)
{
List emp = (List) obj;
string empDetalils = string.Format("EmployeeID {0} And Employee Name {1} And GetType is {2}",
emp[0].EmployeeID, emp[0].EmployeeName, obj.GetType());
return empDetalils;
}
#endregion
}
}
Employee.cs
namespace wcfServer
{
[DataContract]
public class Employee
{
[DataMember]
public int EmployeeID { get; set; }
[DataMember]
public string EmployeeName { get; set; }
}
}
Client side:
toWcfServer.cs
namespace ClientWS
{
public class toWcfServer : IService1
{
#region Implementation of IService1
public string ParseObject(object obj)
{
try
{
wcfServerService.Service1Client client = new Service1Client();
string strEmployee = client.ParseObject(obj);
client.Close();
return strEmployee;
}
catch (Exception ex)
{
return ex.InnerException.ToString();
}
}
#endregion
}
}
Form1.cs
private void button1_Click(object sender, EventArgs e)
{
toWcfServer toServer = new toWcfServer();
List listEmployees = new List();
listEmployees.Add(new Employee(){EmployeeID = 10, EmployeeName = "PEPEK"});
textBox1.Text = toServer.ParseObject(listEmployees);
}
what is wrong in the code?
Hi,
Thanks for going through my article.
In your code you just need to change following lines:
IService1.cs
namespace wcfServer
{
// NOTE: If you change the interface name “IService1” here, you must also update the reference to “IService1” in Web.config.
[ServiceContract]
[ServiceKnownType(typeof(Employee))] //Earlier it was List
public interface IService1
{
[OperationContract]
string ParseObject(object obj);
}
}
Because your ServiceMessage contains Employee object which .NET f/w don’t knows….so you just need to introduce your Employee object to .NET f/w and [ServiceKnownType(typeof(Employee))] does the same.
Feel free to get back to me if still it doesn’t work.
Happy Coding,
Kiran
Thanks kiran , Great article it worked for me.
This topic helped me to solve my issue… Thanks
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