Question

it’s first time while iam working on wcf soap services for iOS application , em getting problem when trying to send xml to server using post method my iOS side code looks like that

NSString *soapMessage = [NSString stringWithFormat:@"<SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\"><SOAP-ENV:Body><SaveAllRecords33><xmlData></xmlData></SaveAllRecords33></SOAP-ENV:Body></SOAP-ENV:Envelope>"];

NSURL *url = [NSURL URLWithString:@"http://webservice.net2survey.com/servicejson.svc/SaveAllRecord33"];
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:url];                        
NSString *msgLength = [NSString stringWithFormat:@"%d", [soapMessage length]];             

[theRequest addValue: @"text/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[theRequest addValue: @"urn:ServiceJSON/SaveAllRecords33" forHTTPHeaderField:@"SOAPAction"];
[theRequest addValue: msgLength forHTTPHeaderField:@"Content-Length"];
[theRequest setHTTPMethod:@"POST"];    
[theRequest setHTTPBody: [soapMessage dataUsingEncoding:NSUTF8StringEncoding]];

NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];

and on .net side it’s likes that

[WebInvoke(Method = "POST", 
           BodyStyle = WebMessageBodyStyle.WrappedRequest, 
           ResponseFormat = WebMessageFormat.Json)] 
[OperationContract] 
public string SaveAllRecords33(string xmlData) 
{ 
    //DataContractSerializer
    dataContract = new DataContractSerializer(typeof(string)); 
    XmlDocument xmlDoc = new XmlDocument(); 
    xmlDoc.LoadXml(xmlData);

    JavaScriptSerializer objSerialiver = new JavaScriptSerializer();
    return "{\"Answer\":" + objSerialiver.Serialize(xmlDoc.InnerXml) + "}"; 
}

when aim going to hit this url it’s showing some errors as showing bellow

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"><s:Body><s:Fault><faultcode xmlns:a="http://schemas.microsoft.com/net/2005/12/windowscommunicationfoundation/dispatcher">a:InternalServiceFault</faultcode><faultstring xml:lang="en-US">Root element is missing.</faultstring><detail><ExceptionDetail xmlns="http://schemas.datacontract.org/2004/07/System.ServiceModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance"><HelpLink i:nil="true"/><InnerException i:nil="true"/><Message>Root element is missing.</Message><StackTrace>   at System.Xml.XmlTextReaderImpl.ThrowWithoutLineInfo(String res)&#xD;
   at System.Xml.XmlTextReaderImpl.ParseDocumentContent()&#xD;
   at System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean preserveWhitespace)&#xD;
   at System.Xml.XmlDocument.Load(XmlReader reader)&#xD;
   at System.Xml.XmlDocument.LoadXml(String xml)&#xD;
   at WcfService.ServiceJSON.SaveAllRecords33(String xmlData)&#xD;
   at SyncInvokeSaveAllRecords33(Object , Object[] , Object[] )&#xD;
   at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]&amp; outputs)&#xD;
   at System.S
2012-09-25 17:50:00.846 Net2Survey_demo[1576:b903] str: erviceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc&amp; rpc)&#xD;
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc&amp; rpc)&#xD;
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc&amp; rpc)&#xD;
   at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</StackTrace><Type>System.Xml.XmlException</Type></ExceptionDetail></detail></s:Fault></s:Body></s:Envelope>

Answer 1

The service itself works, the issue is not in the WCF. If you scroll far right in the stack trace, you’ll see that it says Root element is missing. and that it fails while creating the XmlDocument inside your service.

You are simply sending it an invalid Xml string and it fails to parse.