Generics and collections ... struggling with an implementation
- by mattruma
I am trying to figure out a way to leverage generics so I can make the property Value be an actual type that initialized (not sure if this is the correct way of saying it) when my collection class is created.
I would like to have the syntax be something like:
var list = new ListItemCollection<Guid>(parameters would go here);
I have the following class:
[Serializable]
public class ListItem
{
public object Value { get; set; }
public string Text { get; set; }
public object DataContext { get; set; }
public Nullable<bool> Checked { get; set; }
public ListItem()
{
this.Checked = false;
}
}
I have the following collection:
[Serializable]
public class ListItemCollection : List<ListItem>
{
public ListItem this[object value]
{
get
{
foreach (var child in this)
{
if (child.Value.Equals(value))
return child;
}
return null;
}
}
public bool Contains(object value)
{
foreach (var child in this)
{
if (child.Value.Equals(value))
return true;
}
return false;
}
public void Add(object value, string text)
{
this.Add(value, text, null);
}
public void Add(object value, string text, object dataContext)
{
var child = new ListItem();
child.Value = value;
child.Text = text;
child.DataContext = dataContext;
this.Add(child);
}
public ListItemCollection()
{
}
public ListItemCollection(IEnumerable items,
string displayMember,
string valueMember,
bool showEmptyItem,
string emptyItemText,
object emptyItemValue)
{
if (showEmptyItem)
{
this.Add(emptyItemValue, emptyItemText);
}
foreach (object item in items)
{
object text = null;
object value = null;
text = item.GetType().GetProperty(displayMember).GetValue(item, null);
value = item.GetType().GetProperty(valueMember).GetValue(item, null);
// Add the item
this.Add(value, text.ToString(), item);
}
}
}
