Rewriting this code another way

Camillia
Camillia used Ask the Experts™
on
I'm so stuck on this. I know what the error is but I don't know how to fix it so I'm trying to rewrite it another way.

(this is the error : Unrecognized expression node: ListInit )

The code below gives me a LINQ error. The solution is here but I don't know how to fix it Solution to error

1. This gives me an error:
 public List<SelectListItemWithAttributes> DropDownDatas
         {
            get
            {

                DataClasses1DataContext db = new DataClasses1DataContext();
             

                var DropDownDataItems = (
                    from c in db.states

                    select new SelectListItemWithAttributes()
                    {
                        Text = c.Name,
                        Value = c.Id.ToString(),
                        HtmlAttributes = new Dictionary<string, string> { { "data-countryid", c.country.ToString().ToLower() } }
                   }).ToList();

                DropDownDataItems.Insert(0, new SelectListItemWithAttributes() { Text = "-- Select --", Value = "", HtmlAttributes = new Dictionary<string, string> { { "data-callback", "false" } } });

             return DropDownDataItems;
             

            }
        }

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2. So, I rewrote it this way but this isn't working because I init the list
var myList = new List<SelectListItemWithAttributes>();
and this comes out as empty

public List<SelectListItemWithAttributes> DropDownDatas
         {
            get
            {

                DataClasses1DataContext db = new DataClasses1DataContext();

                var s = from c in db.states
                    select c;

                var myList = new List<SelectListItemWithAttributes>(); //this is wrong

                foreach (var row in s)
                {
                    foreach (var item in myList)
                    {
                        item.Text = row.Name;
                        item.Value = row.Id.ToString();
                        item.HtmlAttributes = new Dictionary<string, string>
                        {
                            {"data-countryid", row.country.ToString().ToLower()}
                        };

                     myList.Add(item);
                    }
                  
                }

               return myList;
                

            }
        }
    }

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And this is the definition of list:

public class SelectListItemWithAttributes : SelectListItem
    {
        public IDictionary<string, string> HtmlAttributes { get; set; }

        
    }

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Mike EghtebasDatabase and Application Developer

Commented:
While I am trying the simplified version (without --select--, etc), take a look at this:

private void PopulateMyListBox()
{
DataClasses1DataContext db = new DataClasses1DataContext();
ListItem[] s = (from c in db.states
                           select new ListItem(c.name)).ToArray();

           cmbox1.Items.AddRange(outputs);
}

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Thank you so much for taking a look. I've been trying to get this done all afternoon. I was about to try something else.

I need this back in there. I think this is what throws the error

  item.HtmlAttributes = new Dictionary<string, string>
                        {
                            {"data-countryid", row.country.ToString().ToLower()}
                        };
Yes, this line causes the error. I just took it out and it runs without but i need that back.

                     
  HtmlAttributes = new Dictionary<string, string> { { "data-countryid", c.country.ToString().ToLower() } }

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In this code. It's a LINQ error so there has to be a different way of doing this..
var DropDownDataItems = (
                    from c in db.states

                    select new SelectListItemWithAttributes()
                    {
                        Text = c.Name,
                        Value = c.Id.ToString(),
                        HtmlAttributes = new Dictionary<string, string> { { "data-countryid", c.country.ToString().ToLower() } }
                    }).ToList();

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Mike EghtebasDatabase and Application Developer

Commented:
I tried what I gave you using a database and it populates the drop box. I am kind of new to LINQ.

So, populating the control works with a data table. I am assuming your coding upto db.states is correct. If it is then it should work for you as well.

Did you try it as I had it? Please give it a try.

Mike
Yes, as you have it works. But I need that line of code back. That's what breaks it. I'll continue my search for an answer.
Mike EghtebasDatabase and Application Developer

Commented:
Is it suppose to add something to the drop box? if so, how the final data should look like?
it should look like this

<option value="1" data-countryid="US">MO</option>
I tried it like this but got an error that index must be within the bounds of list.

var s = from c in db.states
                    select c;

                var myList = new List<SelectListItemWithAttributes>();
   foreach (var row in s)
                {
                    myList.Insert(row.Id, new SelectListItemWithAttributes() { Text = row.Name, Value = row.Id.ToString(), HtmlAttributes = new Dictionary<string, string> { { "data-ccountryid", row.country } } });
                }

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Mike EghtebasDatabase and Application Developer

Commented:
Can you add this dictionary data to your db.states before hand (before it gets to LINQ)? It seems you are trying to add two fields to the drop box which I think will not work.

I am testing something new, brb
I have it in db.states. I need to add it to the dropdown as an extra attribute. It's ok. Someone else might be able to look at this question.
Mike EghtebasDatabase and Application Developer

Commented:
my dictionary was called listBoxes, change it to whatever you have. But it seems your dictionary is anonymous.

foreach (var d in listBoxes)
        {
            DropDownList1.Items.Insert(0, ">" + d.Value.ToString());
        }

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This code comes after the first one. Remove ">" from code. I wanted to have a visual confirmation items added.

FYI, I will away for a while.

Mike
Database and Application Developer
Commented:
DataClasses1DataContext db = new DataClasses1DataContext();
ListItem[] s = (from c in db.states
                           select new ListItem(c.name)).ToArray();

           ddllist.Items.AddRange(outputs);

ddllist.DisplayMember="EnterFieldNameHere";   //like "State"
ddllist.ValueMember="EnterRecordIDFieldHere"; // like "StateID"

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that might work I'll try it and add the custom htmlattribute back and see
Mike EghtebasDatabase and Application Developer

Commented:
DataClasses1DataContext db = new DataClasses1DataContext();
ListItem[] s = (from c in db.states
                           select new ListItem(c.StateID, c.State)).ToArray();

           ddllist.DataSource =s;

ddllist.DisplayMember="EnterFieldNameHere";   //like "State"
ddllist.ValueMember="EnterRecordIDFieldHere"; // like "StateID"

?

With ddllist.Items.Add it adds a single item, but with ddllist.Datasource =Table1, it add both items (ID and Name).

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