How to convert enum to a bool for DataBinding in Winforms?

Question

Is it possible to do this? I need to use:

this.ControlName.DataBindings.Add (...)

so I can't define logic other than bind my enum value to a bool .

For example:

(DataClass) Data.Type (enum)

EDIT:

I need to bind Data.Type which is an enum to a checkbox's Checked property. So if the Data.Type is Secure , I want the SecureCheckbox to be checked, through data binding.

Answer 1

Winforms binding generates two important and useful events: Format and Parse .

The format event fires when pulling data from a source into a control and the Parse event fires when pulling data from a control back into the data source.

If you handle these events you can alter/retype the values going back and forth during binding.

For example here are a couple of example handlers for these events:

 public static void StringValuetoEnum<T>(object sender, ConvertEventArgs cevent)
 {
      T type = default(T);
      if (cevent.DesiredType != type.GetType()) return;
      cevent.Value = Enum.Parse(type.GetType(), cevent.Value.ToString());
 }

 public static void EnumToStringValue<T>(object sender, ConvertEventArgs cevent)
 {
      //if (cevent.DesiredType != typeof(string)) return;
      cevent.Value = ((int)cevent.Value).ToString();
 }

And here is some code attaching these event handlers:

 List<NameValuePair> bts = EnumHelper.EnumToNameValuePairList<LegalEntityType>(true, null);
 this.cboIncType.DataSource = bts;                
 this.cboIncType.DisplayMember = "Name";
 this.cboIncType.ValueMember = "Value";

 Binding a = new Binding("SelectedValue", this.ActiveCustomer.Classification.BusinessType, "LegalEntityType");
 a.Format += new ConvertEventHandler(ControlValueFormatter.EnumToStringValue<LegalEntityType>);
 a.Parse += new ConvertEventHandler(ControlValueFormatter.StringValuetoEnum<LegalEntityType>);
 this.cboIncType.DataBindings.Add(a);

So in your case you can just create a SecEnum to Bool handler for the format event and within that do something like:

 SecEnum se = Enum.Parse(typeof(SecEnum), cevent.Value.ToString());
 cevent.Value = (bool)(se== SecEnum.Secure);

and then reverse that during parse.

Answer 2

Well if you are binding to your class you could always have a property on it like this:

public bool IsSecured
{
   get 
   {
      if (myEnum == SecEnum.Secured)
         return true;
      else 
         return false;
   }
}

Just reverse for the setter if needed.