How to return message in the WCF endpoint?

Question

I have an endpoint:

[ServiceContract]
public interface ICheck
{
        [OperationContract]
        [WebInvoke(Method = "GET", UriTemplate = "check")]
        Task GetCheckAsync();
 }

I don't know how to return a string in the response to this endpoint. I try to return Task object but I can't instaniate it.

Question: How to return an object containing message to the requester(frontend)?

Answer 1

Try like this

1) If you want to return an object

 [ServiceContract]
 public interface ICheck
 {
    [OperationContract]
    [WebInvoke(Method = "GET", UriTemplate = "check")]
    Task<objectname> GetCheckAsync();
 }

and while defining

public class HelloService : ICheck
{
    public async Task<objectname> GetCheckAsync()
    {
       // do your operation and return the object
    }
}

2) If You Want to return a string

 [ServiceContract]
 public interface ICheck
 {
    [OperationContract]
    [WebInvoke(Method = "GET", UriTemplate = "check")]
    Task<string> GetCheckAsync();
 }

and while defining

public class HelloService : ICheck
{
    public async Task<string> GetCheckAsync()
    {
       // do your operation and return the string
    }
}

For more clarification you can check the following Link for example

Example