StrataFrame Forum » StrataFrame Application Framework - V1 » WinForms (How do I?) » Combobox with single char value and meaningful displayvalue

Combobox with single char value and meaningful displayvalue

Charles R Hankey — Wed, 22 Feb 2012 15:54:54 GMT

I've always used BOs or Enums for my lookup combodropdowns

Now I have a backend column that is Char(1) and constrained to C D A ( Change, Delete, Add )

I want to display those three choices to the user and bind to C D or A based on pick

Looking for the cleanest way to populate a dropdown CBO and have the bound value be C D or A and the full word displayed.

I'm sure it's not hard but it's not coming to me with 55+ hours in already on the work week :w00t:

BONUS Round :

Need manually populated combo that acts like a three state checkbox

Display TRUE, FALSE, NO CHANGE and have the backend value set to true, false and null

( I have defined the bit column that accepts nulls with nullable generic in the BO Mapper - Correct?)

TIA

RE: Combobox with single char value and meaningful displayvalue

Charles R Hankey — Wed, 22 Feb 2012 15:54:54 GMT

Probably should add I really could have done this with automatic get;set;

RE: Combobox with single char value and meaningful displayvalue

Charles R Hankey — Wed, 22 Feb 2012 15:46:09 GMT

Hi Marsha - Life is good - still at Dow Jones - Doing all C# now and loving it.

Here is how I ended up creating a dropdown that would bind to single character string

First created a custom class

[code]

        public class actionType  // used for cboActionToPerform
             {
             private string _actionval;
             private string _displayval;
             public string ActionVal
                 {
                 get { return _actionval; }
                 set { _actionval = value; }
                 }
             public string DisplayVal
                 {
                 get { return _displayval; }
                 set { _displayval = value; }                }
             public actionType(string actionval, string displayval)
                 {
                 _actionval = actionval;
                 _displayval = displayval;
             }

[/code]

then in the contstructor of the form

[code]

...
 
      List<actionType> Actions = new List<actionType>();
             Actions.Add(new actionType("C", "Change"));
             Actions.Add(new actionType("A", "Add"));
             Actions.Add(new actionType("D", "Delete"));

             this.cboAction.DataSource = Actions;
             this.cboAction.DisplayMember = "DisplayVal";
             this.cboAction.ValueMember = "ActionVal";

[/code]

Working well.

Say Hi to Andy for me.

RE: Combobox with single char value and meaningful displayvalue

Marcia G Akins — Wed, 22 Feb 2012 13:26:57 GMT

[quote][b]Charles R Hankey (2/17/2012)[/b][hr]
Looking for the cleanest way to populate a dropdown CBO and have the bound value be C D or A and the full word displayed.
[/quote]

Hi Charles.

Long time no see. How is everything going?

The way that I handle this is by using by standard lookup tables - lookup_hdr for the lookup categories and lookup_dtl for the lookups by category. Now, lookup_dtl has a varchar(10) field for a code in addition to the pk, description, display order number, acitve flag and default flag. So, in order to do what you want, you just populate the BO and display the description from lookup_dtl and bind to the code. Usually I bind to the pk, of course, but this setup is nice and flexible.

HTH.

-- Marcia