Get field value from item in SPListItemCollection

Question

I am confused with SPQuery. How can I use it to get listitem values. Let's say I have a list "Cinema" with 20 columns but i only want 4.

• Film ID
• Film Name
• Film Type
• Film Review

How can i get all list items using SPQuery and access them using SPListItemCollection.

Example. not working

spsite site = new site("portal.filmworld.com/abc")
spweb web = site.openweb();
{
   splist li = web.lists["Films"];
   spquery q = new spquery();
   q.query = string.Format("<FieldRef Name='FilmID' /><FieldRef Name='FilmName' /><FieldRef Name='FilmType' /><FieldRef Name='FilmReview' />");

   splistitemcollection items = li.getitems(q);

   foreach(SPListItem item in items)
   {
          string name = item.filmName;     <----   it's not working gives exception of null
   }

}

Answer 1

Try this:

   splist li = web.lists["Films"];
   spquery q = new spquery();
   q.Query=""; //Enter a caml query here if you would like to restrict your results...
   q.ViewFields = string.Concat(
                                   "<FieldRef Name='FilmID' />",
                                   "<FieldRef Name='FilmName' />",
                                   "<FieldRef Name='FilmType' />",
                                   "<FieldRef Name='FilmReview' />");
   q.ViewFieldsOnly = true; // Fetch only the data that we need

   splistitemcollection items = li.getitems(q);

   foreach(SPListItem item in items)
   {
         string name = item["FilmName"].toString();

   }

The query is for restricting the items that we want to return, not the data returned for each item.

Answer 2

You do as you always do with ListItems. For example:

string name = item["filmName"].toString();

For not nullable types (like DateTime) you should do a null check:

DateTime aDate = item["myDateColumn"] != null ? DateTime.parse(item["myDateColumn"].toString()) : null;

(OK, I know there exists better ways but this is pretty generic)

So, basically not so hard :)

Answer 3

The way you wrote q.query is not the usual way to write the query. A normal query would be where you add your conditions in CAML syntax so that you return a subset of the items based on your criteris; if you are looking to get back all the items from a list, then you don't need SPQuery. Here is an example of an SPQuery:

q.Query = "<Where><Eq><FieldRef Name='FilmID'/><Value>Some random film id</Value></Eq></Where>"

Here is a tutorial: SPQuery in SharePoint 2010

The other thing is you wouldn't access the field FilmName like you did above, UNLESS you used something like Linq to SharePoint/Entity Framework (which is a totally separate discussion!). Try using item["FilmName"] instead. Here is another tutorial: Sharepoint 2010 – How best to reference a Column (Field) from an SPListItem

Hope this helps!