Call a WCF Rest Service in an ASP.Net Web Form

[Rhyeca Riley]

Hey everyone,

The title basically says it all. I have created a rest service using a WCF Service Application in C# and I am trying to call the service in an ASP.net Web Application (Web Form). Here are some things I have tried as well as my config file for the restful service. Please let me know if anything else is needed to understand the problem and how to solve it. Also, I should mention the first method was "working" until recently. Thank you for your help!

            int h = Convert.ToInt16(Height.Text);
            int w = Convert.ToInt16(Weight.Text);
            RestBMI.Service1Client newRest = new RestBMI.Service1Client();
            RestBMILabel.Text = Convert.ToString(newRest.BMI(w, h));
            RestHealthLabel.Text = Convert.ToString(newRest.HealthIndicator(w, h));

This provides this error "System.InvalidOperationException: 'Could not find default endpoint element that references contract 'RestBMI.IService1' in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element.'"

            WebClient newWebClient = new WebClient();
            string serviceURL = string.Format("http://localhost/Service1.svc/BMI/BodyMeasurements?weight={0}&height={0}", w, h);
            byte[] data = newWebClient.DownloadData(serviceURL);
            Stream newStream = new MemoryStream(data);
            var reader = new StreamReader(newStream);
            RestBMILabel.Text = reader.ReadToEnd();

this provide this error: System.Net.WebException: 'Unable to connect to the remote server'

webconfig:

<?xml version="1.0" encoding="utf-8"?>
<configuration>

  <appSettings>
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true" />
  </appSettings>

  <system.web>
    <compilation debug="true" targetFramework="4.7.2" />
    <httpRuntime targetFramework="4.7.2"/>
  </system.web>

  <system.serviceModel>

    <services>
      <service name="RestBMI.Service1" behaviorConfiguration="ServiceBehaviors">
        <endpoint name="" contract="RestBMI.IService1" binding="webHttpBinding" behaviorConfiguration="web">
        </endpoint>
      </service>
    </services>

    <behaviors>
      <serviceBehaviors>
        <behavior name ="ServiceBehaviors">
          <!-- To avoid disclosing metadata information, set the values below to false before deployment -->
          <serviceMetadata httpGetEnabled="true"/>
          <!-- To receive exception details in faults for debugging purposes, set the value below to true.  Set to false before deployment to avoid disclosing exception information -->
          <serviceDebug includeExceptionDetailInFaults="false"/>
        </behavior>
      </serviceBehaviors>

      <endpointBehaviors>
        <behavior name="web">
          <webHttp/>
        </behavior>
      </endpointBehaviors>
    </behaviors>

    <protocolMapping>
      <add binding="basicHttpsBinding" scheme="https" />
    </protocolMapping>

    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" />
  </system.serviceModel>


  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true"/>
    <!--
        To browse web app root directory during debugging, set the value below to true.
        Set to false before deployment to avoid disclosing web app folder information.
      -->
    <directoryBrowse enabled="true"/>
  </system.webServer>

</configuration>

[Stephan van Hulst]

Hello Rhyeca,

The first snippet won't work because your web.config doesn't provide an endpoint address for your WCF service.

I'm not exactly sure why the second snippet won't work, although in general it's not a good idea to access a WCF service using WebClient. Instead, for a declarative approach use a service reference in your client project (this is likely what you already did to make your first snippet work), or for a programmatic approach use ChannelFactory or for RESTful web services use HttpClient.

First make sure the service is running by browsing to http://localhost/Service1.svc. This should give you a basic WCF page that links to service descriptors. If it is running, add the endpoint to your web.config:
<services>  <service name="RestBMI.Service1" behaviorConfiguration="ServiceBehaviors">    <endpoint contract="RestBMI.IService1" binding="webHttpBinding" behaviorConfiguration="web" address="http://localhost/Service1.svc"/>  </service> </services>
Let us know if this solves your problem. If not, remove all configuration related to the web service from your client project, and try to add a new service reference through Visual Studio's service reference wizard.

[Rhyeca Riley]

So I tried both of your suggestions and I am still getting the same "System.InvalidOperationException: 'Could not find default endpoint element that references contract 'RestBMI.IService1' in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element'" error. I removed the service reference and added the address="Service.svc" (wasnt able to add the localhost portion as I was getting errors).

[Rhyeca Riley]

Here is what my IService1.cs file looks like. Not sure if this would help with understanding how I am setting up the Restful service. (The ... after the healthindicator and BMI are to avoid getting flagged for cheating (if this were to get flagged).

    
        [OperationContract]
        [WebGet(UriTemplate = "HealthIndicator/.....", BodyStyle = WebMessageBodyStyle.Wrapped, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)]
        string HealthIndicator(int weight, int height);

        [OperationContract]
        [WebGet(UriTemplate = "BMI/....", BodyStyle = WebMessageBodyStyle.Wrapped, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)]
        double BMI(int weight, int height);

[Stephan van Hulst]

Presumably you also have an implementation of that interface on your server side.

Can you show us the implementation class (minus the method bodies), and can you also show us the service interface header and its attributes?

You should have a web.config on both the server-side (because it is a WCF application) and on the client-side (because it is an ASP.NET application). Please show us both web.config files.

How did you add the service reference, by the way? Did you use the wizard provided by Visual Studio?

[Rhyeca Riley]

Implementation of interface

 public class Service1 : IService1
    {
        public string HealthIndicator(int weight, int height)
        {
            
        }

        public double BMI(int weight, int height)
        {

        }
    }

Client side web.config. To answer your question yes I used the wizard to add the service reference.

<?xml version="1.0" encoding="utf-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  https://go.microsoft.com/fwlink/?LinkId=169433
  -->
<configuration>
  <configSections>
    <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
      <section name="BMI.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </sectionGroup>
  </configSections>
  <system.web>
    <compilation debug="true" targetFramework="4.7.2"/>
    <httpRuntime targetFramework="4.7.2"/>
    <pages>
      <namespaces>
        <add namespace="System.Web.Optimization"/>
      </namespaces>
      <controls>
        <add assembly="Microsoft.AspNet.Web.Optimization.WebForms" namespace="Microsoft.AspNet.Web.Optimization.WebForms" tagPrefix="webopt"/>
      </controls>
    </pages>
  </system.web>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> 
      <dependentAssembly>
        <assemblyIdentity name="Antlr3.Runtime" publicKeyToken="eb42632606e9261f"/>
        <bindingRedirect oldVersion="0.0.0.0-3.5.0.2" newVersion="3.5.0.2"/>
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed"/>
        <bindingRedirect oldVersion="0.0.0.0-11.0.0.0" newVersion="11.0.0.0"/>
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35"/>
        <bindingRedirect oldVersion="0.0.0.0-1.6.5135.21930" newVersion="1.6.5135.21930"/>
      </dependentAssembly>      
    </assemblyBinding>
  </runtime>
  <system.codedom>
    <compilers>
      <compiler language="c#;cs;csharp" extension=".cs"
        type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
        warningLevel="4" compilerOptions="/langversion:default /nowarn:1659;1699;1701"/>
      <compiler language="vb;vbs;visualbasic;vbscript" extension=".vb"
        type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
        warningLevel="4" compilerOptions="/langversion:default /nowarn:41008 /define:_MYTYPE=\"Web\" /optionInfer+"/>
    </compilers>
  </system.codedom>
  <system.serviceModel>
    <bindings />
    <client />
  </system.serviceModel>
  <applicationSettings>
    <BMI.Properties.Settings>
      <setting name="BMI_localhost_SoapBMIWebService" serializeAs="String">
        <value>http://localhost:59883/SoapBMIWebService.asmx</value>
      </setting>
    </BMI.Properties.Settings>
  </applicationSettings>
</configuration>

[Rhyeca Riley]

Hey all, I solved this by doing the HttpWebRequest method which worked out great. Thank you all for your help and guidance!