C# LINQ: How to check object value of a listbox item and set color accordingly

I was wondering if this was possible. Here is the code that populates a listbox:

var allHolds =
                from a in db.Record_HoldDatas
                join f in db.LUT_Flavors on a.Flavor equals f.ID
                into flavorNames
                where开发者_如何学编程 a.HoldStatus == "Open"
                from grouped in flavorNames
                select new { a.HoldID, a.DateOpened, grouped.flavor, a.NonConformingItem, 
                Caption = a.HoldID + " - " + a.Package + " " + grouped.flavor };

            lbxHoldCaption.DataSource = allHolds;
            lbxHoldCaption.DisplayMember = "Caption";

what I want to do is write a loop that goes through each object in the listbox and uses a couple values to do some math. If the math result is a certain value, then I want it to change that item's background color.

I'm not sure how to use a foreach loop with this. Since the listbox is actually bound to a reference full of anonymous types

More specifically, this is what im doing: One of the values in the object returned from the query is datetime "DateOpened" I want to subtract todays datetime with that to determine the hours elapsed. i was using something like this

DateTime now = DateTime.Now;
DateTime then = //retrieved from query object
TimeSpan span = now - then;

I was hoping to do this whole thing with something like

foreach(Object obj in allHolds)
{
     then = obj.DateOpened;
     span = now - then;

     if(span.TotalHours >= 48)
     {
          obj.BackColor = Color.Red;
     }
}

but obviously this doesnt work because the referencing is all borked. Can someone help me out?

try this

var allHolds =
            from a in db.Record_HoldDatas
            join f in db.LUT_Flavors on a.Flavor equals f.ID
            into flavorNames
            where a.HoldStatus == "Open"
            from grouped in flavorNames
            select new { a.HoldID, a.DateOpened, grouped.flavor, a.NonConformingItem, 
            Caption = a.HoldID + " - " + a.Package + " " + grouped.flavor, 
            BackColor = (DateTime.Now - a.DateOpened).TotalHours >= 48 ? "Red" : "Blue" };

and

        lbxHoldCaption.DataSource = allHolds;
        lbxHoldCaption.DisplayMember = "Caption";
        lbxHoldCaption.DataBindings.Add("BackColor", allHolds,"BackColor");

foreach (ListItem xx in ListBox1.Items)
    {

        if (Convert.ToInt32(xx.Value) == 3)
        {

            xx.Attributes["style"] = "background-color:red;";

        }
     }

dont forget about those properties of ListBox : DataTextField="Caption" DataValueField="DateOpened"

Simple, use the var keyword, that way you don't need to specify the type explicitly.

foreach(var obj in allHolds)
{
     then = obj.DateOpened;
     span = now - then;

     if(span.TotalHours >= 48)
     {
          obj.BackColor = Color.Red;
     }
}