Question

I have two ListBox in my winforms application, I assigne a datasource for both of them as follow:

private void MakeMeasurementUnits()
{
    var units = new List<MeasurementUnit>
                    {
                        new MeasurementUnit {Name = "Current", SiUnit = "A"},
                        new MeasurementUnit {Name = "Voltage", SiUnit = "V"},
                        new MeasurementUnit {Name = "Time", SiUnit = "s"},
                        new MeasurementUnit {Name = "Temprature", SiUnit = "°C"}
                    };

    lbxXunit.DataSource = units;
    lbxYunit.DataSource = units;
}

The strange thing is (or maybe because it is my first time!!), in the form when I click on items of one of these lisboxes, the same item in the second listbox gets selected as well. Is this a default behaviour? how to prevent this? If this is default behaviour, what is useful about it?

I found the quick remedy to be making two different datasources (same thing with another name)

Answer 1

The listbox seems to cache the binding source. This is default behavior. If you want to avoid this, the easy way is to create a copy of the list to bind to the second data source:

lbxXunit.DataSource = units;
lbxYunit.DataSource = units.ToList();

This is useful when you have multiple views of the same data and want to synchronize the selection of these items.