Retrieving selected enum from dropdown list

I am binding an enumeration to a dropdown list in asp.net 4.0 C#

Enumernation is:

public enum Frequency
{
    [Description("Select a frequency")]
    None,

    [Description("Every Hour/Mintues")]
    EveryHourOrMintues, 

    [Description("Previous Day Data")]
    PreviousDayData,

    [Description("Once a week")]
    OnceaWeek
}

On the selection of a value from the dropdown I want to get the enum value in return: I am doing it like:

Frequency selectedFrequency;
foreach (Frequency f in Enum.GetValues(typeof(Frequency)))
{
    if (f.ToString().Equals(this.dropDownListFrequency.SelectedValue))
    {
        selectedFrequency = f;
        break;
    }
}

It is working but definitely a poor way I guess, by looping through each of the items in enum (even though enum is very small)

How can I retrieve selected enum like:

Frequency selectedValue = Enum.GetValues(typeof(Frequency)).Cast<Frequency>().Select(f => f.ToString().Equals(this.dropDownListFrequency.SelectedValue));

I understand that above given code has casting issue.

Edit For more information, here is how I am binding enum to dropdown list

var frequencies =  Enum.GetValues(typeof(Frequency)).Cast<Frequency>().Select(f => new
            {
                Text = f.ToDescriptiveTextUsingAttributes(),
                Value = f.ToString()
            });
this.dropDownListFrequency.DataSource=frequencies ;
this.dropDownListFrequency.DataTextField = "Text";
this.dropDownListFrequency.DataValueField = "Value";

ToDescriptiveTextUsingAttributes() is an extension method that returns value of Description attribute of enum

---

If the value of the dropdown list is the enum's integer representation (eg 0,1,2...), then you can simply cast it back to the enum:

Frequency f = (Frequency)int.Parse(dropDownListFrequency.SelectedValue);

If the value of the dropdown list is the enum's string representation (eg "None", "EveryHourOrMintues"...), then you can use Enum.Parse() :

Frequency f = (Frequency)Enum.Parse(
    typeof(Frequency), dropDownListFrequency.SelectedValue);

---

You can extend the ListItem class to store the actual Frequency enum object and add those specialized ListItem objects to dropDownListFrequency.Items . When you retrieve dropdownListFrequency.SelectedItem you can get the actual value selected.

class FrequencyListItem : System.Web.UI.WebControls.ListItem.ListItem {
    private Frequency _Frequency;

    public Frequency Frequency {
        get { return _Frequency }
    }

    public FrequencyListItem (Frequency f) {
        this._Frequency = f;
        this.Text = f.ToDescriptiveTextUsingAttributes();
        this.Value = f.ToString();
    }
}

Since all your elements in the Items property are your specialized class, you can easily retrieve your enum value as follows:

Frequency selectedFrequency = ((FrequencyListItem )this.dropDownListFrequency.SelectedItem).Frequency;

Edit: You can still even use the same binding model you have with some minor changes:

var frequencies =  Enum.GetValues(typeof(Frequency)).Cast<Frequency>().Select(f => new FrequencyListItem()
            {
                //FrequencyListItem will auto set this in the constructor for you!
                //Text = f.ToDescriptiveTextUsingAttributes(),
                //Value = f.ToString()
            });
this.dropDownListFrequency.DataSource=frequencies;
this.dropDownListFrequency.DataTextField = "Text";
this.dropDownListFrequency.DataValueField = "Value";

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