Represents class for SELECT HTML (drop-down) control. Most important property is Items array property.

ComboBox SmartCL.Controls.ComboBox   TW3ComboBox = class(TW3CustomControl)   Public methods:   procedure Clear;   function Add(aValue: String): Integer;   procedure Remove(aIndex: Integer);   function IndexOf(aValue: String): Integer;   Properties: public   property Items[index: Integer]: String read getItem write setItem;   property Values[index: Integer]: Variant read getValue write setValue;   property Count: Integer read getCount;   property SelectedIndex: Integer read getSelIndex write setSelIndex;

Unit: SmartCL.Controls.ComboBox.pas

Hierarchy

TObject

TW3TagObj

TW3Component

TW3MovableControl

TW3CustomControl

TW3ComboBox

Properties
Count
Items
SelectedIndex
Values
Methods
Add
Clear
Remove
IndexOf

Usage Typical usage of this control is to first add new items by using Add method. Every new item create corresponding OPTION DOM object. Values array may be also set in order to specify value attribute for each option (See also: Values). Example:

W3ComboBox1.Add('Norway');
W3ComboBox1.Values[W3ComboBox1.Count - 1]:= '47';

Second step is usually reading SelectedIndex property. Example:

MyString:= W3ComboBox1.Values[W3ComboBox1.SelectedIndex];

Properties

Count

Determine number of items in strings array.

property Count: Integer read getCount;

Items

Sets and gets item at specified index.

property Items[index: Integer]: String read getItem write setItem;

Example:

var  i: Integer;begin  for i:= 0 to W3ComboBox1.Count - 1 do  begin    if W3ComboBox1.Items[i] = W3EditBox1.Text then    begin      // do something    end;  end;end;

SelectedIndex

Specifies currently selected item.

property SelectedIndex: Integer read getSelIndex write setSelIndex;

Values

Specifies value for item at same position inside array. If value is set, every OPTION will get value attribute.

property Values[index: Integer]: Variant read getValue write setValue;

Example:

W3ComboBox1.Add('Ann');
W3ComboBox1.Values[0]:= '0';
W3ComboBox1.Add('Ben');W3ComboBox1.Values[1]:= '1';
W3ComboBox1.Add('Philip');W3ComboBox1.Values[2]:= '2';

Output:

<select id="OBJ1" class="TW3ComboBox" style="visibility: visible; display: inline-block; position: absolute; 
overflow: hidden; left: 16px; top: 288px; width: 128px; 
height: 32px;">    <option value="0">Ann</option>    <option value="1">Ben</option>    
<option value="2">Philip</option></select>

Methods

Add

Add new item into strings array.

function Add(aValue: String): Integer;

aValue

string

Value to be added to array.

Example:

W3ComboBox1.Add(W3EditBox1.Text);

Clear

Delete all items from items array and set Count property to 0.

procedure Clear;

Remove

Remove item at specified index from items array.

procedure Remove(aIndex: Integer);

aIndex

Integer

Item's index requesting to be removed.

Remarks:

It is recommended to check if item exists before deletion.

Example:

// Delete currently selected (showing) 
itemW3ComboBox1.Remove(W3ComboBox1.SelectedIndex);

IndexOf

Return index (zero-based) of first occurrence of specified string inside items array. If there is no specified string within array result will be -1.

function IndexOf(aValue: String): Integer;

aValue

string

String to be found inside items array.

Example:

if W3ComboBox1.IndexOf(W3EditBox1.Text) <> -1 then
begin  
  ShowMessage('Item fond!');
end;