Here is my Combo Box
you should try '.' instead of Value, it should pick it up as binding to the object as it has no property name
comboBox1.DisplayMemberPath = ".";
Try this:
<ComboBox Height="40" VerticalAlignment="Stretch" SelectedValuePath="Key" DisplayMemberPath="Value" x:Name="comboBox1" FontSize="25"/>
var source = new Dictionary<string, double>();
source.Add("Item1", 0.4);
source.Add("Item2", 0.3);
source.Add("Item3", 0.1);
source.Add("Item4", 0.1);
var formateDSource = new Dictionary<string, string>();
foreach (var item in source)
{
formateDSource.Add(string.Format("[{0}, {1}]", item.Key, item.Value), item.Key);
}
comboBox1.ItemsSource = source;