C# – Passing a List from Silverlight using WCF

asp.netcnetsilverlightwcf

I have my WCF service defined as follows
[ServiceContract]
public interface IService1
{
[OperationContract]
IList GetMyTable();

    [OperationContract]
    void SendMyTable(List<RatePositions> ratePositions);

    [OperationContract]
    void SendString(string value);
}

When I call GetMyTable() from my SilverLight app it works fine, it brings a List of ratePositions into my app.
SendString() also works fine which sends a string from my app.

SendMyTable(List ratePositions) does not work which should sent a List of ratePositions from my app.

The error I get is:
The remote server returned an unexpected response: (404) Not Found

Any ideas why this method does not work but the others do?

Best Answer

The problem may be the message size problem with WCF. Look at both the clientconfig file that is created in your silverlight project as well as the web.config in your server project to make sure the size of the data you're returning is not too large.

The 404 error is a catch all for any WCF failure. Can you debug the server code to see if its getting that far?

Related Solutions

C# – Should ‘using’ directives be inside or outside the namespace

There is actually a (subtle) difference between the two. Imagine you have the following code in File1.cs:

// File1.cs
using System;
namespace Outer.Inner
{
    class Foo
    {
        static void Bar()
        {
            double d = Math.PI;
        }
    }
}

Now imagine that someone adds another file (File2.cs) to the project that looks like this:

// File2.cs
namespace Outer
{
    class Math
    {
    }
}

The compiler searches Outer before looking at those using directives outside the namespace, so it finds Outer.Math instead of System.Math. Unfortunately (or perhaps fortunately?), Outer.Math has no PI member, so File1 is now broken.

This changes if you put the using inside your namespace declaration, as follows:

// File1b.cs
namespace Outer.Inner
{
    using System;
    class Foo
    {
        static void Bar()
        {
            double d = Math.PI;
        }
    }
}

Now the compiler searches System before searching Outer, finds System.Math, and all is well.

Some would argue that Math might be a bad name for a user-defined class, since there's already one in System; the point here is just that there is a difference, and it affects the maintainability of your code.

It's also interesting to note what happens if Foo is in namespace Outer, rather than Outer.Inner. In that case, adding Outer.Math in File2 breaks File1 regardless of where the using goes. This implies that the compiler searches the innermost enclosing namespace before it looks at any using directive.

C# – Silverlight & WCF: Max message size

If you are sending out a large number of items from WCF, also make sure that maxItemsInObjectGraph is a relatively high number

<behaviors>
   <serviceBehaviors>
      <behavior name="YourBahvior">
         <dataContractSerializer maxItemsInObjectGraph="6553600"/>
      </behavior>
   </serviceBehaviors>
</behaviors>

Best Answer

Related Solutions

C# – Should ‘using’ directives be inside or outside the namespace

C# – Silverlight & WCF: Max message size

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