Casting Combobox.SelectedItem back to DateTime causes "Specified cast is not valid."

I have the following code which appears correctly populates a combobox

    class Hour
    {
        public string shownHour {get;set;}
        public DateTime atime {开发者_如何学Goget;set;}
    }

    (...)

    DateTime now = new DateTime();
    now = DateTime.Now;

    List<Hour> hours = new List<Hour>
        {
            new Hour{shownHour = "8:00 AM", atime = new DateTime(now.Year, now.Month, now.Day, 8,0,0)},
            new Hour{shownHour = "8:30 AM", atime = new DateTime(now.Year, now.Month, now.Day, 8,30,0)}
        };

    comboBox1.DataSource = hours;
    comboBox1.ValueMember = "atime";
    comboBox1.DisplayMember = "shownHour";

I'm seeing the "8:00 AM" and "8:30 AM" correctly populate and selectable in the combobox. However, when I attempt to retrieve the ValueMember in the ComboBox_SelectedIndexChanged event I'm getting a "Specified cast is not valid." error. I can't seem to retrieve it back with the following code.

DateTime StartTime = (DateTime) comboBox1.SelectedItem;

In the debugger, I'm seeing the atime from the combobox.SelectedItem and it does appears to be formatted as a DateTime type but I can't seem to cast it back. Am I approaching this problem incorrectly?

Solution: as @Cj S pointed out below, Combobox.SelectedItem was returning the Hour type where I thought it would be returning data of Hour.atime of type DateTime. Using the solution given gave the correct information.

You can't cast a string to a DateTime. Use DateTime.Parse instead.

If your combo is DataBinded then you need to do the following.

int intId = ((Priority)comboPriority.SelectedValue).Id;

Where Priority is my Entity Class

Oops...

I was completely wrong. You need to get the SelectedValue instead of the SelectedItem like this:

DateTime StartTime = (DateTime) comboBox1.SelectedValue;

I believe that your selected item is the of the type Hour and you are trying to cast it as a DateTime I believe your code should be somethign like

DateTime StartTime = (DateTime) comboBox1.SelectedItem.atime;