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How can I store more than one piece of information in a ComboBox item?

Hi all,
Sorry if this is a stupid question, but how should I store more than one piece of information in a ComboBox Item?
For example, say I have 3 entries:

'Red'
'Blue'
'Green'

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but when I select the item, I want a 'hidden' field to be available, such as:

'R'
'B'
'G'

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Ideally I would like to do something like:

MyCombo.AddItem('Red', 'R');
MyCombo.AddItem('Green', 'G');
MyCombo.AddItem('Blue', 'B');

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and be accessed:

HiddenValue := MyCombo.Items[MyCombo.SelIndex].Value;

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Any ideas how I can achieve something resembling this?
Any help would be appreciated...
Best regards,
James

wellhole

You could bind your combobox to a datasource (ie MyCombo.Datasource = table) and set the display and value members to the columns in the table.

table = new datatable
table.columns.add("description")
table.columns.add("value")
table.rows.add("desc1", "value1")
table.rows.add("desc2", "value2")
table.rows.add("desc3", "value3")

combo.displaymember = "description"
combo.valuemember = "value"
combo.datasource = table

When you want to get the value of the selection you would simply use MyCombo.SelectedValue.

Member_2_99151

ASKER

Thanks for the suggestion but this is required for Delphi....

wellhole

My mistake. This new website makes it much more difficult to tell what kind of questions I'm reading.

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Thommy

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Member_2_99151

ASKER

Thanks...
That makes the selection filter correctly, but how do I stop the 'Red=R' from being displayed in the dropdown? It should only display 'Red'

Member_2_99151

ASKER

Ah!
I can owner draw the ComboBox:

procedure TForm1.ComboBox1DrawItem(Control: TWinControl; Index: Integer; Rect: TRect; State: TOwnerDrawState);
begin
    ComboBox1.Canvas.TextRect(Rect, Rect.Left, Rect.Top, ComboBox1.Items.Names[Index]);
end;

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Is this a 'correct' way to achieve this?

Thommy

if you don't want both, name and value, displayed in your combobox I suggest to use a separate stringlist...

  sl: TstringList;  //global var

  ComboBox1.AddItem('Red',nil);
  ComboBox1.AddItem('Green',nil);
  ComboBox1.AddItem('Blue',nil);

  //create separate stringlist with names and values derived from combobox
  sl:=TStringList.create;  
  sl.AddStrings(combobox1.Items);
  sl[0]:=sl[0]+'=R';
  sl[1]:=sl[1]+'=G';
  sl[2]:=sl[2]+'=B';

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Retrieve data using current combobox item data...

var
  AValue: string;
  AName: string;

//returns value of your current combobox item
AValue :=sl.ValueFromIndex[combobox1.ItemIndex];  

//also returns value of your current combobox item
AValue :=sl.Values[combobox1.Text];

//returns name of your current combobox item
//same as combobox1.Text
AName:=sl.Names[combobox1.ItemIndex];

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Thommy

Using OwnerDraw is also possible, but keep in mind to set style property of your combobox to csOwnerDrawFixed or csOwnerDrawVariable to activate OnDrawItem event...

Member_2_99151

ASKER

Thanks for the help :-)