Expose LinQ generated collection

[Eduardo Lorenzo]

Hi guys.

 

Am playing around with LinQ here, using VS2008Express. And I have this:

 

private void QueryData()
       {
           var peopleOlderThan = from p in people
                                 where p.Birthday < DateTime.Parse(textBox1.Text)
                                 orderby p.Name ascending
                                 select p;

           dataGridView1.DataSource = new BindingSource(peopleOlderThan, null);
        }

 

don't mind the part with the combobox. This statement basically gets data from here:

 

people = new List<Person>();
           people.Add(new Person("Timmy", DateTime.Parse("1/2/1990")));
           people.Add(new Person("Gerald", DateTime.Parse("2/9/1979")));
           people.Add(new Person("Brian", DateTime.Parse("12/29/1973")));

 

This works ok, but I was just wondering if there is a way to expose peopleOlderThan outside of the method? Right now, what I do is put it in a function and return it as IEnumerable.

 

private IEnumerable getList()
       { 
       var peopleOlderThan = from p in people
                                 where p.Birthday < DateTime.Parse(textBox1.Text)
                                 orderby p.Name ascending
                                 select p;
       return peopleOlderThan;
       }

 

all inputs are welcome.

[PlausiblyDamp]

You could try something like

IEnumerable peopleOlderThan;

private void QueryData()
{
peopleOlderThan = from p in people
   where p.Birthday < DateTime.Parse(textBox1.Text)
   orderby p.Name ascending
   select p;

dataGridView1.DataSource = new BindingSource(peopleOlderThan, null);
}

 

You should then be able to access peopleOlderThan in other methods etc. by using a generic IEnumerable at least you also get proper intellisense throughout your code as well.

 

If you are messing with multiple threads then the above code is probably a disaster waiting to happen unless you implement some proper synchronisation .

[Eduardo Lorenzo]

I did this:

 

public ReadOnlyCollection<Person> GetPersons 
{ 
get { return peopleOlderThan.AsReadOnly(); } 
} 

 

and am testing right now. Yes PD, the method you posted does supply intellisense but I heeded you warning and didn't use it. I am creating a "faux" data layer so I won't be sure how it will be consumed by other devs so I really want to be on the safe side of this. Thanks soooo much!