ComboBox

Namespace: Wisej.Web

Assembly: Wisej.Framework (3.5.0.0)

• Control
  • ListControl
    • ComboBox

Represents a combo box control.

C#

public class ComboBox : ListControl, IModified, ILabel, IReadOnly

VB.NET

Public Class ComboBox
    Inherits ListControl
    Implements IModified, ILabel, IReadOnly

Constructors

ComboBox()

Initializes an instance of ComboBox.

ComboBox(onSelectedIndexChanged)

Initializes a new instance of ComboBox class with specific initial settings.

Name	Type	Description
onSelectedIndexChanged	Action<Object, EventArgs>	SelectedIndexChanged handler.

ComboBox(label, onSelectedIndexChanged)

Initializes a new instance of ComboBox class with specific initial settings.

Name	Type	Description
label	String	The initial text to display in the TextBox label.
onSelectedIndexChanged	Action<Object, EventArgs>	SelectedIndexChanged handler.

ComboBox(dataSource, displayMember, valueMember, iconMember, onSelectedIndexChanged)

Initializes a new instance of ComboBox class with specific initial settings.

Name	Type	Description
dataSource	Object	Initial DataSource.
displayMember	String	Initial DisplayMember.
valueMember	String	Initial ValueMember.
iconMember	String	Initial IconMember.
onSelectedIndexChanged	Action<Object, EventArgs>	Optional SelectedIndexChanged handler.

ComboBox(location, size, onSelectedIndexChanged)

Initializes an instance of ComboBox with the given datasource, size, location, and action.

Name	Type	Description
location	Point	Initial location.
size	Size	Initial size.
onSelectedIndexChanged	Action<Object, EventArgs>	Optional SelectedIndexChanged handler.

ComboBox(location, size, dataSource, displayMember, valueMember, iconMember, onSelectedIndexChanged)

Initializes an instance of ComboBox with the given datasource, size, location, and action.

Name	Type	Description
location	Point	Initial location.
size	Size	Initial size.
dataSource	Object	Initial DataSource.
displayMember	String	Initial DisplayMember.
valueMember	String	Initial ValueMember.
iconMember	String	Initial IconMember.
onSelectedIndexChanged	Action<Object, EventArgs>	Optional SelectedIndexChanged handler.

ComboBox(label, location, size, onSelectedIndexChanged)

Initializes an instance of ComboBox with the given datasource, size, location, and action.

Name	Type	Description
label	String	The initial text to display in the TextBox label.
location	Point	Initial location.
size	Size	Initial size.
onSelectedIndexChanged	Action<Object, EventArgs>	Optional SelectedIndexChanged handler.

ComboBox(label, location, size, dataSource, displayMember, valueMember, iconMember, onSelectedIndexChanged)

Initializes an instance of ComboBox with the given datasource, size, location, and action.

Name	Type	Description
label	String	The initial text to display in the TextBox label.
location	Point	Initial location.
size	Size	Initial size.
dataSource	Object	Initial DataSource.
displayMember	String	Initial DisplayMember.
valueMember	String	Initial ValueMember.
iconMember	String	Initial IconMember.
onSelectedIndexChanged	Action<Object, EventArgs>	Optional SelectedIndexChanged handler.

Properties

AllowHtml

Boolean: Returns or sets a value indicating that the control can display html in the Text property. (Default: False)

AutoCompleteMode

AutoCompleteMode: Returns or sets how automatic completion works for the ComboBox. (Default: None)

AutoSize

Boolean: Returns or sets whether the height of the control is set automatically. (Default: True)

CharacterCasing

CharacterCasing: Returns or sets whether the ComboBox control modifies the case of characters as they are typed. (Default: Normal)

DropDownHeight

Int32: Returns or sets the maximum height in pixels of the drop-down portion of the ComboBox. (Default: 400)

Throws:

• ArgumentException The specified value is less than one.

DropDownStyle

ComboBoxStyle: Returns or sets the drop down style of the combo box. (Default: DropDown)

DropDownWidth

Int32: Returns or sets the maximum width in pixels of the drop-down list of the ComboBox. When the value is 0, the drop-down list will grow to fit the largest item. (Default: 0)

Throws:

• ArgumentException The specified value is less than one.

DroppedDown

Boolean: Returns or sets whether the combo box is displaying its drop-down portion.

EnableNativeContextMenu

Boolean: Enables or disables the browser's context menu. (Default: True)

IncrementalSelection

Boolean: Returns or sets whether items are selected incrementally as the user types within a timeout of 1 second. (Default: True)

ItemHeight

Int32: Gets or sets the height of the list items in the drop-down list. When the value is -1, uses the value set in the theme. (Default: -1)

Throws:

• ArgumentOutOfRangeException The assigned value is less than -1; or the assigned value is greater than 500.

Items

ObjectCollection: Returns the collection of the items contained in this ComboBox.

Label

LabelWrapper: Provides a label related to the control.

LabelText

String: Returns or sets the localizable label associated with this control. (Default: "")

LazyLoading

Boolean: Returns or sets whether the items are sent to the client the first time the list is opened and enables the Load event. (Default: False)

MaxLength

Int32: Returns or sets the number of characters a user can type into the ComboBox. (Default: 0)

Throws:

• ArgumentOutOfRangeException The value is less than 0.

ReadOnly

Boolean: Returns or sets whether the control is read-only. (Default: False)

SelectedIndex

Int32: Returns or sets the index of the currently selected item.

Throws:

• ArgumentOutOfRangeException The specified index is less than -1; o the specified index is greater than the number of items in the combo box.

SelectedItem

Object: Returns or sets currently selected item in the ComboBox.

SelectedText

String: Returns or sets the text that is selected in the editable portion of a ComboBox.

SelectionLength

Int32: Returns or sets the number of characters selected in the editable portion of the combo box.

Throws:

• ArgumentException The value was less than zero.

SelectionStart

Int32: Returns or sets the starting index of text selected in the combo box.

Throws:

• ArgumentException The value is less than zero.

Sorted

Boolean: Returns or sets whether the items in the combo box are sorted. (Default: False)

Throws:

• ArgumentException An attempt was made to sort a ComboBox that is attached to a data source.

SpellCheck

Boolean: Returns or sets whether the text in the ComboBox is spell checked by the browser. (Default: False)

Text

String: Returns or sets the text associated with this control. (Default: "")

Tools

ComponentToolCollection: Returns the instance of ComponentToolCollection associated with this control.

Watermark

String: Returns or sets the text to show when the control is empty. (Default: null)

Methods

BeginUpdate()

Not used. Kept for compatibility.

Copy()

Copies the current selection in the text box to the Clipboard.

Cut()

Moves the current selection in the text box to the Clipboard.

EndUpdate()

Not used. Kept for compatibility.

FindString(text)

Returns the index of the first item in the ComboBox that starts with the specified string.

Parameter	Type	Description
text	String	The String to search for.

Returns: Int32. The zero-based index of the first item found; returns -1 if no match is found.

FindString(text, startIndex)

Returns the index of the first item in the ComboBox beyond the specified index that contains the specified string. The search is not case sensitive.

Parameter	Type	Description
text	String	The String to search for.
startIndex	Int32	The zero-based index of the item before the first item to be searched. Set to -1 to search from the beginning of the control.

Returns: Int32. The zero-based index of the first item found; returns -1 if no match is found, or 0 if the text parameter specifies Empty.

FindStringExact(text)

Finds the first item in the combo box that matches the specified string.

Parameter	Type	Description
text	String	The String to search for.

Returns: Int32. The zero-based index of the first item found; returns -1 if no match is found, or 0 if the text parameter specifies Empty.

FindStringExact(text, startIndex)

Finds the first item after the specified index that matches the specified string.

Parameter	Type	Description
text	String	The String to search for.
startIndex	Int32	The zero-based index of the item before the first item to be searched. Set to -1 to search from the beginning of the control.

Returns: Int32. The zero-based index of the first item found; returns -1 if no match is found, or 0 if the text parameter specifies Empty.

Paste()

Replaces the current selection in the text box with the contents of the Clipboard.

Select(start, length)

Selects a range of text in the editable portion of the ComboBox.

Parameter	Type	Description
start	Int32	The position of the first character in the current text selection within the text box.
length	Int32	The number of characters to select.

SelectAll()

Selects all the text in the editable portion of the ComboBox.

Events

AutoComplete

HandledEventHandler Fired before the Validating event when DropDownStyle is set to DropDown or Simple.

The application may implement a different way to select the item when the user types a text and the ComboBox is validated. Set e.Handled to true to override the standard behavior.

this.comboBox1.AutoComplete += (s, e) =>
{
  if (this.comboBox1.Text == "T")
  {
    this.compoBox1.SelectedIndex = 1;
    e.Handled = true;
  }
}

DropDown

EventHandler Fired when the drop-down portion of a ComboBox is shown.

DropDownClosed

EventHandler Fired when the drop-down portion of the ComboBox is no longer visible.

DropDownStyleChanged

EventHandler Fired when the DropDownStyle property has changed.

Load

EventHandler Fired when the drop-down list is first opened and the LazyLoading property is true.

When LazyLoading is true An application may fill the items at any time prior to the drop-down list being opened, or while processing the DropDown or Load event.

ReadOnlyChanged

EventHandler Fired when the value of the ReadOnly property has changed.

SelectedIndexChanged

EventHandler Fired when the SelectedIndex property has changed.

SelectedItemChanged

EventHandler Fired when the SelectedItem property has changed.

SelectionChangeCommitted

EventHandler Fired when the selected item has changed and that change is displayed in the ComboBox.

SortedChanged

EventHandler Fired when the Sorted property has changed.

ToolClick

ToolClickEventHandler Fired when a ComponentTool is clicked.

Inherited By

Name	Description
DataGridViewComboBoxEditingControl	Represents a ComboBox control that can be hosted in a DataGridViewComboBoxCell.
ListViewComboBox	The TreeViewComboBox control represents a UserComboBox control with a ListView as the drop down panel.
TreeViewComboBox	The TreeViewComboBox control represents a UserComboBox control with a TreeView as the drop down panel.
UserComboBox	The UserComboBox control represents a ComboBox control with a custom panel that drops down when the user clicks the down arrow.

Implements

Name	Description
IBindableComponent	Bindable components implement this interface.
IDropTarget	Controls that support drag & drop operations implement this interface.
ILabel	Provides access to the LabelWrapper associated with the controls that implement this interface.
IReadOnly	Provides access to the ReadOnly property for coontrols that support the read-only mode.
IModified	Provides access to the Modified property and ModifiedChanged event for controls that implement this interface.
IValidation	Provides access to the validation events and properties property for controls that support validation.
IWisejComponent	All wisej components implement this interface.
IWisejControl	All wisej controls derived from the Control class must implement this interface.
IWisejSerializable	Allows an object to serialize itself.