Error: Cannot have two operations in the same contract with the same name
Error: Cannot have two operations in the same contract with the same name. This issue comes into picture when you try to overload methods in WCF service & also when you define OperationContract NAME attributes are replicated across a service. Find solution for Error: Cannot have two operations in the same contract with the same name
Learn on Error: Cannot have two operations in the same contract with the same name
Scenario 1:
Lets say I have an Interface as IMyService which defines two methods as PrintString()
In the below example, 1st method takes parameter as string & the 2nd method takes no parameter.
So in this it would generate error as "Cannot have two operations …. etc"
[ServiceContract]
public interface IMyService
{
[OperationContract]
[WebGet(UriTemplate = "PrintString/strValue/{s}")]
string PrintString(string s);
[OperationContract]
[WebGet(UriTemplate = "PrintString")]
string PrintString();
}
So to fix this we need to define names to operationcontract i.e.
[OperationContract(Name = "PrintString1?)] as follows
[ServiceContract]
public interface IMyService
{
[OperationContract(Name = "PrintString1?)]
[WebGet(UriTemplate = "PrintString/strValue/{s}")]
string PrintString(string s);
[OperationContract(Name = "PrintString2?)]
[WebGet(UriTemplate = "PrintString")]
string PrintString();
}
Scenario 2:
Lets say I have an Interface as IMyService which defines two methods (PrintFirstName(string s), PrintLastName()) one with Single parameter & other with no parameters & here the function names are also different but the OperationContract name is same to both the methods as shown below. Incase also we will get to see the "Cannot have two opetations …. etc"
In this case both the methods are defined with same name (PrintName) for OperationContract as
[ServiceContract]
public interface IMyService
{
[OperationContract(Name = "PrintName")]
[WebGet(UriTemplate = "PrintFirstName/strValue/{s}")]
string PrintFirstName(string s);
[OperationContract(Name = "PrintName")]
[WebGet(UriTemplate = "PrintLastName")]
string PrintLastName();
}
By this time I hope you have figured it out on How to fix this.
Yes you are right by changing OperationContract name as follows
[ServiceContract]
public interface IMyService
{
[OperationContract(Name = "PrintFirstName")]
[WebGet(UriTemplate = "PrintFirstName/strValue/{s}")]
string PrintFirstName(string s);
[OperationContract(Name = "PrintLastName")]
[WebGet(UriTemplate = "PrintLastName")]
string PrintLastName();
}
Happy Kooding… Hope this helps!
Wow !! That is superb .... really nice. Thanks Mr. Prokash.