样式下拉列表中选定的项目

Question

I checked for this before posting here and didn't find anything for my problem.

I have a drop down list to which I manually append an item at the end. I want to use some other color for this item, say red, to distinguish it from other items. I can do this part. However, when I select the item, the text in the drop down's selected item is not red. I am not sure if there is any way to access it in order to apply style to it.

This is what I used (assuming the "value" of this last item in drop down is 0):

ListItem li = ddl1.Items.FindByValue("0");

if (null != li)
{
    li.Attributes.Add("style", "color:red");
}

the above works coloring last item red. The following didn't work when I select this last item and want the selected item to displayed in the same red color:

ListItem li = ddl1.Items.FindByValue("0");

if (null != li)
{
    li.Attributes.Add("style", "color:red");

    if (li.Selected)
        ddl1.SelectedItem.Attributes.Add("style", "color:red");
    else
        ddl1.SelectedItem.Attributes.Add("style", "color:black");
}

Neither did this (this actually colors all list items red if I select the last item):

ListItem li = ddl1.Items.FindByValue("0");

if (null != li)
{
    li.Attributes.Add("style", "color:red");
    ddl1.Style["color"] = "red";
}

Answer 1

to use a pure CSS way, add this CSS

#ddl1>option:checked  {
  background-color: red;
}

and in your C#, you can add and select the new option. Let me know if this needs to change course