Android访问调用Webservice

public String InvokeWebService(String serviceURL,String NameSpace,String methodName,String soapaction,String[] parnames,Object[] parvalues)
{
String _ret="";
try{
SoapObject request = new SoapObject(NameSpace,methodName);
if(parnames!=null && parnames.length>0)
{
for(int i=0;i<parnames.length;i++)
{
request.addProperty(parnames[i],parvalues[i]);
}
}
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER12);
envelope.bodyOut = request;
envelope.dotNet=true;
//envelope.setOutputSoapObject(request);
HttpTransportSE ht = new HttpTransportSE(serviceURL);
ht.debug=true;
try{
ht.call(null, envelope);

if(envelope.getResponse()!=null){
SoapPrimitive response = (SoapPrimitive) envelope.getResponse();
_ret=response.toString();
}
} catch(Exception e){
_ret=e.getMessage();
}
}catch(Exception e){
_ret=e.getMessage();
}
return _ret;
}