linq: how to get records update within 1 minute?

I have a table which has a col开发者_如何转开发umn called lastUpdateTime, datetime type. How to do a query that will list all records that been updated within last 1 minute?

DataContext dc=new DataContext();

from a in dc.Acccounts
where a.lastUpdateTime //how to write this line?
select a;

Well this might be dependent on timezone data that can get tricky but assuming simplicity you can do..

from a in dc.Accounts
where a.lastUpdateTime >= DateTime.Now.AddMinutes(-1)
select a;

I am sure there are about 900 ways to skins this cat. I am making a lot of assumptions here but this should get you running.

1. First I created a console application as I wasn't clear what you were using (assuming wpf or silverlight)

2. Created a person class with your LastUpdateDate:

   public class Person
   {
       public int ID { get; set; }
       public string FirstName { get; set; }
       public DateTime LastUpdateDate { get; set; }
       public Person()
   
       {
       }
   {
   

3. Populated a People list with arbitrary data. Peformed the query using a lambda expression. Look up Timespan if the subtraction isn't making sense. Notice 2 of them have an update date of greater than 1 minute ago.

   static void Main(string[] args)
   {   
       List<Person> People = new List<Person>();
       People.Add(new Person() { ID = 1, FirstName = "Test1", LastUpdateDate = DateTime.Now.AddMinutes(-10) });
       People.Add(new Person() { ID = 2, FirstName = "Test2", LastUpdateDate = DateTime.Now.AddMinutes(-5) });
       People.Add(new Person() { ID = 3, FirstName = "Test3", LastUpdateDate = DateTime.Now });
   
       var result = People.Where(p => (DateTime.Now - p.LastUpdateDate).Minutes <= 1);
   
       foreach (Person p in result)
       {
           Console.WriteLine(p.FirstName);
       }
   
       Console.ReadLine();
   }
   

4. Result should be "Test3"

Cheers

Matt