return html from wcf service

Question

I have a web service from which I need to return a string containing html. This html is the markup for a Select control (for use in jqGrid search filters), e.g.

<select><option id='1'> value 1 </option></select>  

My WCF web service contains a method that returns this value as a string...

public string GetLeadTypeSelect()
{
    return "<select><option id='1'> value 1 </option></select>";
}  

and the contract for this method is :

[OperationContract]
[WebInvoke(Method = "GET",
    BodyStyle = WebMessageBodyStyle.Bare,
    ResponseFormat = WebMessageFormat.Json)]
string GetLeadTypeSelect();  

My problem is that escape characters are inserted into the string so rendering the returned HTML useless - the service returns this :

"<select><option id='1'> value 1 <\/option><\/select>"  

The quotation marks and the escaped '/' in the closing <option> and <select> tags both cause problems.

jqGrid uses the returned HTML to display the dropdown...

filterModel: [
    { label: 'Type', name: 'type', stype: 'select', surl: '../../../Services/Leads/GetLeads.svc/GetLeadTypeSelect' },

So, my question is, how to I return pure HTML back to the client from this web service so that it can be inserted into my HTML page?

Thanks in advance for any help, Colin.

Answer 1

I know this is an old post, but for a service that will only be hosted in IIS, here is an easy way to return html:

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Required)]
public Stream getHtml()
{
    // get the html
    var html = DoSomethingToGetHtml();  //Not a built-in .Net method ;)

    // we want our result interpreted as plain html
    WebOperationContext.Current.OutgoingResponse.ContentType = "text/html; charset=utf-8";

    // create a stream from our html because trying to return a string adds an extra header tag
    //      to the response.  Returning a stream returns the html by itself
    var result = new MemoryStream(Encoding.UTF8.GetBytes(html));

    // return the result
    return result;
}

This code requires the following in the web.config hosting the service:

<system.serviceModel>
    <!-- enable HttpContext.Current by setting aspNetCompatibilityEnabled=true-->
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true"/>

    <behaviors>
        <endpointBehaviors>
            <behavior name="webHttpEnabled">              
                <webHttp/>
            </behavior>
        </endpointBehaviors>
    </behaviors>
    ...
<system.serviceModel>

In the configuration for the service, set behaviorConfiguration="webHttpEnabled".

Returning html in this way limits the reusability of the service a bit, but it's an easy way to solve the problem if you're reasonably sure the service will always be hosted in IIS.