How can I show just distinct names (from my model) in my view?
Question
Problem
How can I return back just the distinct names in my view? I can't cast the string returned by my distinct() method back to an Inumerable object.
For simplification, if you see a person named John Smith in the database, we assume all quotes from John Smith are from the same person.
Code
Data
id name quote
1 Finn Mathematical
2 Jake Aw, man!
3 Shredder Tonight, I dine on turtle soup.
4 Shredder Nooooo
Model
namespace Quotes_Sample.Models
{
public class QuoteDB
{
public int Id { get; set; }
public string name { get; set; }
public string quote { get; set; }
public bool IsSelected { get; set; }
}
public class QuoteDBContext : DbContext
{
public DbSet<QuoteDB> Quotes { get; set; }
}
}
Controller
private QuoteDBContext db = new QuoteDBContext();
// GET: Quotes
public ActionResult Index()
{
return View(db.Quotes.ToList());
}
View
@model IEnumerable<Quotes_Sample.Models.QuoteDB>
@{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
</head>
<body>
<p>
@Html.ActionLink("Create New", "Create")
</p>
@using (Html.BeginForm("SubmitSelected", "Quotes", FormMethod.Post, new { encType = "multipart/form-data", name="myform"}))
{
<table class="table">
<tr>
<th>
@Html.DisplayNameFor(model => model.name)
</th>
</tr>
@foreach (var item in (IEnumerable<Quotes_Sample.Models.QuoteDB>)Model.Select(x => x.name).Distinct())
{
<tr>
<td>
@Html.DisplayFor(modelItem => item.name)
</td>
</tr>
}
</table>
}
</body>
</html>
Error
An exception of type 'System.InvalidCastException' occurred in App_Web_cied5w21.dll but was not handled in user code
Additional information: Unable to cast object of type '<DistinctIterator>d__81`1[System.String]' to type 'System.Collections.Generic.IEnumerable`1[Quotes_Sample.Models.QuoteDB]'.
Attempts
- I can just remove the casting and have duplicates, but it's really ugly.
- I thought about writing a temp variable that remembers last name in loop, if same it breaks. That is just plain gross? Seems hacky too.
- Just having 1 name to 1 quote relationship in my database, but that avoids the problem completely.
- This , which actually brought me to this problem.
This below:
<table class="table"> <tr> <th> @Html.DisplayNameFor(model => model.name) </th> </tr> @foreach (string name in Model.Select(x => x.name).Distinct()) { <tr> <td> @Html.DisplayText(name); </td> </tr> } </table>But that really weirds me out. It gives me the following:
name ; ; ;
Thanks for your patience and assistance.
1 answers
solution1
2 ACCPTED 2014-10-07 18:58:00
You can get Distinct records by name using:
Model.GroupBy(x => x.name).Select(x => x.First())
But you should do this in your Controller , not View .
Also you can use DistinctBy method:
Model.DistinctBy(x => x.name)
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