Display Nested Data (hierarchy), MVC3 - asp.net-mvc-3

Question

I have a model like as follows:
public class Category
{
[Key]
public int Id { get; set; }
[StringLength(200), Required, DataType(DataType.Text)]
public string Title { get; set; }
[Display(Name = "Parent Category")]
public int? ParentId { get; set; }
[DisplayFormat(NullDisplayText = "Root")]
public virtual Category ParentCategory { get; set; }
public virtual ICollection<Category> ChildCategories { get; set; }
}
Which is hierarchical in nature, 'ParentId' reference to 'Id' as self referencing. With this, I'm trying to display the Data as follows:
+--------+-----------------+
| S. No | Name |
+--------+-----------------+
| 1 | Parent One |
+--------+-----------------+
| 1.1 | Child-1 of One |
+--------+-----------------+
| 1.2 | Child-2 of One |
+--------+-----------------+
| 2 | Parent Two |
+--------+-----------------+
| 2.1 | Child-1 of Two |
+--------+-----------------+
| 3 | Parent Three |
+--------+-----------------+
Please help me on this.

Answer 1

You can count the Total Child Numbers using an group by parentId and then count
Here is my solution
Define an ViewModel
public class CategoryViewMoel
{
public IEnumerable<ParentCategoryInfo> parentCategoryInfo { get; set; }
public int SN { get; set; }
public int ChildSN { get; set; }
}
public class ParentCategoryInfo
{
public int? ParentId { get; set; }
public int TotalChild { get; set; }
}
In The Controller
var model = new CategoryViewMoel();
var parentCategory = from r in db.Categories
where r.ParentCategory != null
group r by r.ParentId into newGroup
select new ParentCategoryInfo
{
TotalChild = newGroup.Count(),
ParentId = newGroup.Key,
};
model.SN = 1;
model.ChildSN = 1;
model.parentCategoryInfo = parentCategory;
Lastly In your View
<table>
<thead>
<tr>
<th>S. No</th>
<th>Name</th>
</tr>
</thead>
<tbody>
#foreach (var parent in Model.parentCategoryInfo)
{
<tr>
<td>#Model.SN </td>
<td>Parent #Model.SN</td>
</tr>
for (var i = Model.ChildSN; i <= parent.TotalChild; i++)
{
<tr>
<td>#Model.SN.#i</td>
<td>Child - #i of #Model.SN</td>
</tr>
Model.ChildSN = 1;
Model.SN++;
}
</tbody>
The Mapping form numerical to words can be done by building an customized helper function to achieve this, there are plenty of examples in SO
converting numbers in to words C#