Adding a default SelectListItem - asp.net-mvc

Question

public IEnumerable<SelectListItem> GetList(int? ID)
{
return from s in db.List
orderby s.Descript
select new SelectListItem
{
Text = s.Descript,
Value = s.ID.ToString(),
Selected = (s.ID == ID)
};
}
I return the above to a view and populate a DropDownList. I would like to add a default SelectListItem (0, "Please Select..") to the above linq result before it is returned to the view. Is this possible?

Answer 1

return new[] { new SelectListItem { Text = ... } }.Concat(
from s in db.List
orderby s.Descript
select new SelectListItem
{
Text = s.Descript,
Value = s.ID.ToString(),
Selected = (s.ID == ID)
});

Answer 2

As you are using ASP.NET MVC, you can do this in the view by specifying a value for the optionLabel parameter of the DropDownField method of the HtmlHelper - e.g:
htmlHelper.DropDownList("customerId", selectList, "Select One");
Putting this type of code in your UI layer is probably more appropriate than having it in the data layer. One downside to doing this is that your select box will have an empty string value, not a "0" for the 'Select One' option, but that is not really a problem as you can treat this as a null value if your controller action method can accept a nullable int for the relevant parameter - e.g.
public ActionResult DoSomething(int? customerId)
{
if(customerId != null)
{
// do something with the value
}
}

Answer 3

var list = from s in db.List
orderby s.Descript
select new SelectListItem
{
Text = s.Descript,
Value = s.ID.ToString(),
Selected = (s.ID == ID)
};
list.Insert(0, new SelectListItem { Text = "Please Select...", Value = string.Empty });
return list;

Answer 4

firt put your default value in the list
list.add(your default list item)
and then do list.addrange(linq select query)
cheers

Answer 5

Here is what I did, I read my values from an XML file into an IList. I then inserted a new record into the IList at position 0. Then make a select list from the IList.
IList< MY_DATA > mydata = (from tmp in myXML.Descendants("R").ToList()
select new MY_DATA
{
NR = tmp.Attribute("NR").Value,
NA = tmp.Attribute("NA").Value
}).ToList<MY_DATA>();
mydata.Insert(0, new My_DATA() { NR = "", NA = "--Click to Select--" });
SelectList mylist = new SelectList(mydata, "NR", "NA");

Answer 6

After I reviewed many questions, and I don't find what i'm looking for.I don't need many lines of code to just have a simple drowpdown. so I want to share with you what I use and it easy and simple.. ( specially if you don't want to use and Entity Framework..
using System.Web.Mvc;
SelectList(IEnumerable items, string dataValueField, string dataTextField);
For Example:
in Controller add :
SelectList slTitle = new SelectList(Query.SelectAllTitle(), "TitleID", "TitleName");
ViewBag.TitleSelectList = slTitle;
in View add :
#Html.DropDownList("TitleSelectList", "--please select--")

Answer 7

This is just for people who are using Webpages framwork (not MVC and webform) with Razor V2 and C#, you need do
#Html.DropDownList("category", "Please select", listData)
Note: OptionalLabel need to be the middle parameter.
Equivalent would be add a SelectListitem to your list data:
var list=db.Query("select id, name from dbtable");
List<SelectListItem> listData = new List<SelectListItem>();
listData.Add(new SelectListItem
{
Text = "Please select",
Value = "",
});
foreach(var item in list) {
listData.Add(new SelectListItem {
Text = item.Name,
Value = item.id,
Selected = isSelected
});
}
#Html.DropDownList("play" , listData)