Question

I would like to query with linq some xml file. There are some required and some optional elements. Only required is name – everything else is optional.
If there is some NULL for example cageCode = NULL – it doesnt select anything – I need to add to List of strings – “” – I tried it like below, but it doesnt work. When I have everything filled it works fine, when there is something NULL it doesnt save to list anything.
Could you help me how to set “” to list where is null element?
Thanks!

var queryManufacturer = from dataManufaturer in input.Identification.Manufacturers.Manufacturer
                                                select
                                                new
                                                { 
                                                    dataManufaturer.name,
                                                    dataManufaturer.cageCode,
                                                    dataManufaturer.FaxNumber,
                                                    dataManufaturer.URL.OriginalString
                                                };

                foreach (var a in queryManufacturer)
                {
                    data.Add(a.name);
                    if (a.cageCode == null) data.Add("");
                    else data.Add(a.cageCode);
                    if (a.FaxNumber == null) data.Add("");
                    else data.Add(a.FaxNumber);
                    if (a.OriginalString == null) data.Add("");
                    else data.Add(a.OriginalString);
                }

It throws me a null exception if is some of elements in xml file missing – I dont wanna get this exception – I would like just add empty string beside missing element

Answer 1

try this in your Linq to XML query:

select new
{ 
  name = dataManufaturer.name ?? "",
  cageCode = dataManufaturer.cageCode ?? "",
  FaxNumber  = dataManufaturer.FaxNumber  ?? "",
  OriginalString = dataManufaturer.URL!=null ?  dataManufaturer.URL.OriginalString : ""
};