asked on

Rewriting this code another way

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 Eghtebas

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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Camillia

ASKER

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()}
};

Camillia

ASKER

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 Eghtebas

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

Camillia

ASKER

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 Eghtebas

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

Camillia

ASKER

it should look like this

<option value="1" data-countryid="US">MO</option>

Camillia

ASKER

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 Eghtebas

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

Camillia

ASKER

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 Eghtebas

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

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Mike Eghtebas

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Camillia

ASKER

that might work I'll try it and add the custom htmlattribute back and see

Mike Eghtebas

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).