Disable asp.net dropdownlist specific Iitems - asp.net

Question

I have a dropdownlist with few items which bind in code behind. I populate dropdownlist from below query.
Select ID, Name, IsGroup from TempTable
i set DataTextField = "Name" and DataValueField = "ID"
Now i want to disable some items based on "IsGroup" value in DataBound event. How can i access this "IsGroup" column.
For Each item As ListItem In dd.Items
If (What i will compare here = "N") Then
item.Attributes.Add("disabled", "disabled")
End If
Next
Regards

Answer 1

protected void Page_Load(object sender, EventArgs e)
{
var data = GetData();
List<ListItem> items = new List<ListItem>();
foreach (DataRow row in data.Rows)
{
var item = new ListItem()
{
Value = row["Id"].ToString(),
Text = row["Name"].ToString()
};
if (row["IsGroup"].ToString() != "N")
{
item.Attributes.Add("disabled", "disabled");
}
items.Add(item);
}
this.DropDownList1.Items.AddRange(items.ToArray());
}
ref: make drop down list item unselectable

Answer 2

You are doing 2 activities
Fetching data from the database
populating the list item and attaching property/properties to the list item element
Method 1 : Primarily to understand the different operations involved.
class SurroundingClass
{
class Example1
{
public int ID { get; set; }
public string Name { get; set; }
public string IsGroup { get; set; }
}
public void PopulateExample1()
{
// Separate Sections for Database and Dropdown Manipulation
// Database operation
var cs = System.Configuration.ConfigurationManager.ConnectionStrings("CS").ConnectionString;
string sql = "Select ID, Name, IsGroup from TempTable";
SqlConnection conn = new SqlConnection(cs);
SqlCommand cmd = new SqlCommand(sql, conn);
var dr = cmd.ExecuteReader();
List<Example1> e1 = new List<Example1>();
while (dr.Read)
{
var e = new Example1();
e.ID = dr.GetInt32(0);
e.Name = dr.GetString(1);
e.IsGroup = dr.GetString(2);
e1.Add(e);
}
dr.Close();
conn.Close();
// Populate Dropdown
foreach (var i in e1)
{
var li = new ListItem(i.Name, i.ID);
if (i.IsGroup == "Y")
li.Attributes.Add("disabled", "disabled");
ddlExample1.Items.Add(li);
}
}
}
Method 2 : Squeezing the operations in Method 1 together
public void PopulateExample2()
{
// Database Operation and Dropdown Manipulation together
var cs = System.Configuration.ConfigurationManager.ConnectionStrings("CS").ConnectionString;
string sql = "Select ID, Name, IsGroup from TempTable";
SqlConnection conn = new SqlConnection(cs);
SqlCommand cmd = new SqlCommand(sql, conn);
var dr = cmd.ExecuteReader();
while (dr.Read)
{
var li = new ListItem(dr.GetString(1), dr.GetInt32(0));
if (dr.GetString(2) == "Y")
li.Attributes.Add("disabled", "disabled");
ddlExample2.Items.Add(li);
}
dr.Close();
conn.Close();
}
Please note that there can be several variations to the solution, this being only one of them.