You will need to use the WinJS.xhr object to call your SOAP web service. Not to mention that you want to do many details about the soap request, so I created a little dummy code that you need to fill out with your own parameters:
WinJS.xhr({
type: "GET",
user: accountSid,
password: authKey,
url: "http://yourWebserviceUrl.com",
headers: { "YourSoapHeaders": "WithTheirValues" },
}).then(success, error);
function succes(response)
{
}
function error(error)
{
}
, url xhr. , . , (, POST), .
MSDN - WinJS.Xhr http://msdn.microsoft.com/en-us/library/windows/apps/hh868282.aspx
( , - SOAP, -)