Class SfComboBox

Represents a control that used to select single or multiple value from the drop down list.

Inheritance
System.Object
BaseControl
SfComboBox
Implements
System.IDisposable
System.ComponentModel.ISupportInitialize
Inherited Members
Namespace: Syncfusion.WinForms.ListView
Assembly: Syncfusion.SfListView.WinForms.dll
Syntax
[ComVisible(true)]
public class SfComboBox : BaseControl, IThemeProvider, IVisualStyle, IDisposable, ISupportInitialize

Constructors

SfComboBox()

Initializes a new instance of the SfComboBox class.

Declaration
public SfComboBox()

Properties

AllowCaseSensitiveOnAutoComplete

Gets or sets a value indicating whether the autocomplete Suggest and SuggestAppend mode should be processed based on case sensitive.

Declaration
public bool AllowCaseSensitiveOnAutoComplete { get; set; }
Property Value
Type
System.Boolean

AllowDropDownResize

Gets or sets a value indicating whether the drop down can be resized.

Declaration
public bool AllowDropDownResize { get; set; }
Property Value
Type
System.Boolean

AllowNull

Gets or sets a value indicating whether null or empty string can be set to SfComboBox.

Declaration
public bool AllowNull { get; set; }
Property Value
Type
System.Boolean
Remarks

If AllowNull is true, the Watermark text will be shown in the SfComboBox. Otherwise, empty string will be shown.

AllowSelectAll

Gets or sets a value indicating whether the select all item can be shown at top of the dropdown to select whole items.

Declaration
public bool AllowSelectAll { get; set; }
Property Value
Type
System.Boolean

AutoCompleteMode

Gets or sets the auto complete mode for SfComboBox.

Declaration
public AutoCompleteMode AutoCompleteMode { get; set; }
Property Value
Type
System.Windows.Forms.AutoCompleteMode

AutoCompleteSuggestDelay

Gets or sets the delay in milliseconds for and .

Declaration
public int AutoCompleteSuggestDelay { get; set; }
Property Value
Type
System.Int32

AutoCompleteSuggestMode

Gets or sets the mode for suggesting the dropdown list of AutoComplete Suggest and SuggestAppend modes.

Declaration
public AutoCompleteSuggestMode AutoCompleteSuggestMode { get; set; }
Property Value
Type
AutoCompleteSuggestMode

BackColor

Gets or sets the background color for the SfComboBox.

Declaration
public Color BackColor { get; set; }
Property Value
Type
System.Drawing.Color

BorderStyle

Gets or sets border style of SfComboBox.

Declaration
public BorderStyle BorderStyle { get; set; }
Property Value
Type
System.Windows.Forms.BorderStyle

CheckedItems

Gets or sets the collection containing the checked items of SfComboBox.

Declaration
public ObservableCollection<object> CheckedItems { get; set; }
Property Value
Type
System.Collections.ObjectModel.ObservableCollection<System.Object>

ComboBoxMode

Gets or sets the display mode for SfComboBox.

Declaration
public ComboBoxMode ComboBoxMode { get; set; }
Property Value
Type
ComboBoxMode
Remarks

The ComboBoxMode cannot be changed while SfComboBox in disabled state.

DataSource

Gets or sets data source of the SfComboBox.

Declaration
public object DataSource { get; set; }
Property Value
Type
System.Object

DefaultSize

Gets default size of the control

Declaration
protected override Size DefaultSize { get; }
Property Value
Type
System.Drawing.Size

DelimiterChar

Gets or sets the delimiter character to separate the multiple selected items in the SfComboBox when the ComboBoxMode is .

Declaration
public string DelimiterChar { get; set; }
Property Value
Type
System.String

DisplayMember

Gets or sets the property to display for the SfComboBox

Declaration
public string DisplayMember { get; set; }
Property Value
Type
System.String

DropDownButton

Gets a button that used to represent the drop down portion of a SfComboBox.

Declaration
public SfButton DropDownButton { get; }
Property Value
Type
SfButton

DropDownControl

Gets the popup control of the SfComboBox.

Declaration
public ComboBoxPopup DropDownControl { get; }
Property Value
Type
ComboBoxPopup

DropDownListView

Gets the list view of SfComboBox.

Declaration
public SfListView DropDownListView { get; }
Property Value
Type
SfListView

DropDownPosition

Gets or sets the position of the dropdown relative to the SfComboBox.

Declaration
public PopupRelativeAlignment DropDownPosition { get; set; }
Property Value
Type Description
PopupRelativeAlignment

The DropDownPosition value. The default value is Center

DropDownStyle

Gets or sets the value that specifies the editing style of the SfComboBox.

Declaration
public DropDownStyle DropDownStyle { get; set; }
Property Value
Type
DropDownStyle

DropDownWidth

Gets or sets the width of the drop-down portion of the SfComboBox.

Declaration
public int? DropDownWidth { get; set; }
Property Value
Type Description
System.Nullable<System.Int32>

An System.Int32 representing the width of the drop-down in pixels. The default value is null, which means the drop-down width is determined automatically.
Remarks

If set to null, the drop-down width automatically adjusts to match the combo box width. When specified, the drop-down will use the defined width instead of the default behavior.

Examples

The following example sets the drop-down width to 200 pixels:

sfComboBox.DropDownWidth = 200;
See Also

EnableToken

Gets or sets a value indicating whether to enable or disable token support in SfComboBox

Declaration
public bool EnableToken { get; set; }
Property Value
Type
System.Boolean

Filter

Gets or sets the predicate to filters the values while typing text in editor portion of the SfComboBox.

Declaration
public Predicate<object> Filter { get; set; }
Property Value
Type
System.Predicate<System.Object>
Remarks

AutoCompleteFilter is supported for System.Collections.IEnumerable collection type datasource. It does not support for DataTable datasource.

Examples
SfComboBox sfComboBox = new SfComboBox();
// Add the list of numbers into the datasource
sfComboBox.DataSource = number;
// Set the predicate to filter the values
sfComboBox.Filter = Search;
bool Search(object item)
{
   int number =  (int)sfComboBox.TextBox.Text;
   if( number > (int) item)
   {
      return true;
   }
}

Font

Gets or sets the font of the text displayed by the control.

Declaration
public Font Font { get; set; }
Property Value
Type
System.Drawing.Font

ForeColor

Gets or sets the foreground color for the SfComboBox.

Declaration
public Color ForeColor { get; set; }
Property Value
Type
System.Drawing.Color

MaxDropDownItems

Gets or sets the maximum drop down items count when drop down is showing.

Declaration
public int MaxDropDownItems { get; set; }
Property Value
Type
System.Int32

Padding

Gets or sets the padding value within the SfComboBox.

Declaration
public Padding Padding { get; set; }
Property Value
Type
System.Windows.Forms.Padding

PreferredSize

Gets the size of a rectangular area into which the control can fit.

Declaration
public Size PreferredSize { get; }
Property Value
Type
System.Drawing.Size

RightToLeft

Gets or sets a value indicating whether control's elements are aligned to support locales using right to left fonts.

Declaration
public override RightToLeft RightToLeft { get; set; }
Property Value
Type
System.Windows.Forms.RightToLeft

SelectedIndex

Gets or sets an index of the selected item SfComboBox.

Declaration
public int SelectedIndex { get; set; }
Property Value
Type
System.Int32

SelectedItem

Gets or sets the currently selected item of SfComboBox.

Declaration
public object SelectedItem { get; set; }
Property Value
Type
System.Object

SelectedItems

Gets or sets the collection of the selected items of SfComboBox.

Declaration
public ObservableCollection<object> SelectedItems { get; set; }
Property Value
Type
System.Collections.ObjectModel.ObservableCollection<System.Object>

SelectedValue

Gets or sets selected value for SfComboBox.

Declaration
public object SelectedValue { get; set; }
Property Value
Type
System.Object
Remarks

The SelectedValue returns the value based on ValueMember is it is defined.

ShowClearButton

Gets or sets a value indicating whether the clear button can be shown in the SfComboBox. When click the clear button, existing selection will clear in SfComboBox.

Declaration
public bool ShowClearButton { get; set; }
Property Value
Type Description
System.Boolean

If ShowClearButton is true, the clear button will be shown in the SfComboBox. Otherwise, false.
Remarks

The clear button will be shown in the SfComboBox for both single selection and multiple selection.

ShowToolTip

Gets or sets a value indicating whether tool tip can be shown when mouse hover on editor portion of the SfComboBox for MultiSelection ComboBox.

Declaration
public bool ShowToolTip { get; set; }
Property Value
Type
System.Boolean
Remarks

Tool tip will be shown when ComboBoxMode is .

Site

Gets or sets the value of site to override deafult value of Text property.

Declaration
public override ISite Site { get; set; }
Property Value
Type
System.ComponentModel.ISite

Style

Gets or sets the style for the SfComboBox elements.

Declaration
public ComboBoxVisualStyle Style { get; set; }
Property Value
Type
ComboBoxVisualStyle

Text

Gets or sets the text associated with SfComboBox.

Declaration
public override string Text { get; set; }
Property Value
Type
System.String

TextBox

Gets a TextBox that used to hold editor portion of the SfComboBox.

Declaration
public TextBox TextBox { get; }
Property Value
Type
System.Windows.Forms.TextBox

ToolTipOption

Gets or sets the options for the tooltip to be displayed when hovering on the control.

Declaration
public ComboBoxToolTipOptions ToolTipOption { get; set; }
Property Value
Type
ComboBoxToolTipOptions

ValueMember

Gets or sets the property to use as the actual value for the items in the SfComboBox

Declaration
public string ValueMember { get; set; }
Property Value
Type
System.String

Watermark

Gets or sets water mark text to SfComboBox.

Declaration
public string Watermark { get; set; }
Property Value
Type
System.String
Remarks

Watermark will be shown if AllowNull is enabled.

Methods

BeginInit()

Signals the object that initialization is starting.

Declaration
public void BeginInit()

BeginUpdate()

Suspends the painting of the control until the EndUpdate() method is called.

Declaration
public void BeginUpdate()

CreateAccessibilityInstance()

Creates a new accessibility object in SfListView.

Declaration
protected override AccessibleObject CreateAccessibilityInstance()
Returns
Type Description
System.Windows.Forms.AccessibleObject

A new System.Windows.Forms.AccessibleObject for the SfComboBox, when AccessibilityEnabled is set as true

Dispose(Boolean)

Releases the unmanaged resources used by the Component and optionally releases the managed resources.

Declaration
protected override void Dispose(bool disposing)
Parameters
Type Name Description
System.Boolean disposing

true to release both managed and unmanaged resources; false to release only unmanaged resources.

EndInit()

Signals the object that initialization is complete.

Declaration
public void EndInit()

EndUpdate()

Resumes the painting of the control suspended by calling the BeginUpdate() method.

Declaration
public void EndUpdate()

GetControlName(String)

Helps to apply the Control Name settings in control

Declaration
public override string GetControlName(string controlName)
Parameters
Type Name Description
System.String controlName

The control name.
Returns
Type Description
System.String

Returns the control name.
Overrides

HideDropDown()

Occurs when drop down is hiding.

Declaration
public void HideDropDown()

HideDropDown(PopupCloseAction)

occurs when drop down is hiding

Declaration
public void HideDropDown(PopupCloseAction value)
Parameters
Type Name Description
PopupCloseAction value

popup close type

InitLayout()

Called after the control has been added to another container.

Declaration
protected override void InitLayout()

IsInputChar(Char)

Process the input key on SfComboBox

Declaration
protected override bool IsInputChar(char charCode)
Parameters
Type Name Description
System.Char charCode

The character input.
Returns
Type Description
System.Boolean

either true or false

OnCanApplyThemeChanged(Boolean)

Helps to apply the CanApplyTheme settings in control

Declaration
public override void OnCanApplyThemeChanged(bool canApplyTheme)
Parameters
Type Name Description
System.Boolean canApplyTheme

Specifies whether to apply the theme or not.
Overrides

OnCanOverrideStyleChanged(Boolean)

Helps to apply the CanOverrideStyle settings in control

Declaration
public override void OnCanOverrideStyleChanged(bool canOverrideStyle)
Parameters
Type Name Description
System.Boolean canOverrideStyle

Specifies whether to override the style or not.
Overrides

OnEnabledChanged(EventArgs)

Occurs after the property of the SfComboBox changed.

Declaration
protected override void OnEnabledChanged(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

A event data.

OnGotFocus(EventArgs)

Occurs when the control got focus.

Declaration
protected override void OnGotFocus(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

Event Args

OnKeyDown(KeyEventArgs)

Occues when key down on SfComboBox

Declaration
protected override void OnKeyDown(KeyEventArgs e)
Parameters
Type Name Description
System.Windows.Forms.KeyEventArgs e

A System.Windows.Forms.KeyEventArgs that contains the event data

OnKeyPress(KeyPressEventArgs)

Occurs when key press on SfComboBox

Declaration
protected override void OnKeyPress(KeyPressEventArgs e)
Parameters
Type Name Description
System.Windows.Forms.KeyPressEventArgs e

A System.Windows.Forms.KeyPressEventArgs that contains the event data

OnLayout(LayoutEventArgs)

To Update SfComboBox child Items Layout.

Declaration
protected override void OnLayout(LayoutEventArgs args)
Parameters
Type Name Description
System.Windows.Forms.LayoutEventArgs args

A System.Windows.Forms.LayoutEventArgs that contains the Layout event data.

OnLostFocus(EventArgs)

Occurs when the control loses focus.

Declaration
protected override void OnLostFocus(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

An System.EventArgs that contains event data.

OnMouseDown(MouseEventArgs)

Occurs when perform the mouse down operation.

Declaration
protected override void OnMouseDown(MouseEventArgs e)
Parameters
Type Name Description
System.Windows.Forms.MouseEventArgs e

A System.Windows.Forms.MouseEventArgs contains event data.

OnMouseEnter(EventArgs)

Activates the mouse enter event for the control

Declaration
protected override void OnMouseEnter(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

Event args

OnMouseLeave(EventArgs)

Activates the mouse leave event for the control

Declaration
protected override void OnMouseLeave(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

Event args

OnMouseMove(MouseEventArgs)

Occurs on Mouse move

Declaration
protected override void OnMouseMove(MouseEventArgs e)
Parameters
Type Name Description
System.Windows.Forms.MouseEventArgs e

Event argument

OnMouseWheel(MouseEventArgs)

Occurs while perform the mouse wheel operations.

Declaration
protected override void OnMouseWheel(MouseEventArgs e)
Parameters
Type Name Description
System.Windows.Forms.MouseEventArgs e

A System.Windows.Forms.MouseEventArgs contains the event data.

OnPaint(PaintEventArgs)

Raises the Paint event.

Declaration
protected override void OnPaint(PaintEventArgs args)
Parameters
Type Name Description
System.Windows.Forms.PaintEventArgs args

A System.Windows.Forms.PaintEventArgs that contains the event data.

OnRightToLeftChanged(EventArgs)

Occurs when right to left property is changed

Declaration
protected override void OnRightToLeftChanged(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

A System.EventArgs that contains the Layout event data.

OnSelectionChangeCommitted(EventArgs)

Raises the SelectionChangeCommitted event.

Declaration
protected virtual void OnSelectionChangeCommitted(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

An EventArgs that contains the event data.
Remarks

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnSelectionChangeCommitted method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Note to Inheritors: When overriding OnSelectionChangeCommitted in a derived class, be sure to call the base class's OnSelectionChangeCommitted method so that registered delegates receive the event.

OnSizeChanged(EventArgs)

Occurs while changing the control size.

Declaration
protected override void OnSizeChanged(EventArgs e)
Parameters
Type Name Description
System.EventArgs e

A event arguments.

OnThemeNameChanged(String)

Helps to apply the ThemeName settings in control

Declaration
public override void OnThemeNameChanged(string themeName)
Parameters
Type Name Description
System.String themeName

The theme name.
Overrides

ProcessCmdKey(ref Message, Keys)

Occurs when key process on SfComboBox

Declaration
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
Parameters
Type Name Description
System.Windows.Forms.Message msg

message of key value
System.Windows.Forms.Keys keyData

One of the System.Windows.Forms.Keys values.
Returns
Type Description
System.Boolean

returns key value

RaiseThemeChanged(Object, ThemeChangedEventArgs)

Raises the ThemeNameChanged and ThemeChanged event when theme name changed.

Declaration
protected override void RaiseThemeChanged(object sender, ThemeChangedEventArgs args)
Parameters
Type Name Description
System.Object sender

The sender value.
ThemeChangedEventArgs args

A ThemeChangedEventArgs contains the event data.
Overrides

ScaleControl(SizeF, BoundsSpecified)

Scales a control's location, size, padding and margin.

Declaration
protected override void ScaleControl(SizeF factor, BoundsSpecified specified)
Parameters
Type Name Description
System.Drawing.SizeF factor

The factor by which the height and width of the control will be scaled.
System.Windows.Forms.BoundsSpecified specified

A System.Windows.Forms.BoundsSpecified value that specifies the bounds of the control to use when defining its size and position.

SetBoundsCore(Int32, Int32, Int32, Int32, BoundsSpecified)

To set bounds of control

Declaration
protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified)
Parameters
Type Name Description
System.Int32 x

Specifies the x location of control
System.Int32 y

Specifies the y location of control
System.Int32 width

Specifies the width of the control
System.Int32 height

Specifies the height of the control
System.Windows.Forms.BoundsSpecified specified

Specifies the bounds of the control

ShowDropDown()

Occurs when drop down is opening

Declaration
public void ShowDropDown()

Events

DropDownClosed

Occurs when the popup is closed.

Declaration
public event EventHandler<DropDownClosedEventArgs> DropDownClosed
Event Type
Type
System.EventHandler<DropDownClosedEventArgs>

DropDownClosing

Occurs when the popup is about to be closed.

Declaration
public event EventHandler<DropDownClosingEventArgs> DropDownClosing
Event Type
Type
System.EventHandler<DropDownClosingEventArgs>

DropDownOpened

occurs when drop down is opened.

Declaration
public event EventHandler DropDownOpened
Event Type
Type
System.EventHandler

DropDownOpening

Occurs when the popup is about to be shown.

Declaration
public event EventHandler<DropDownOpeningEventArgs> DropDownOpening
Event Type
Type
System.EventHandler<DropDownOpeningEventArgs>

SelectedIndexChanged

Occurs when selected index value is changed.

Declaration
public event EventHandler SelectedIndexChanged
Event Type
Type
System.EventHandler

SelectedValueChanged

Occurs when selected value is changed.

Declaration
public event EventHandler SelectedValueChanged
Event Type
Type
System.EventHandler

SelectionChangeCommitted

Occurs when the user changes the selected item, and that change is displayed in the ComboBox.

Declaration
public event EventHandler SelectionChangeCommitted
Event Type
Type
System.EventHandler
Remarks

This event is triggered in the following cases:

  • When the user selects a new item in the list box by clicking or pressing Enter.
  • When the user tabs out of the combo after changing the current text, and validation was successful.

ThemeChanged

Occurs when theme name of the SfComboBox has changed.

Declaration
public event ThemeChangedEventHandler ThemeChanged
Event Type
Type
ThemeChangedEventHandler

ToolTipOpened

Occurs while showing the tooltip for the control.

Declaration
public event EventHandler<ComboBoxToolTipOpenedEventArgs> ToolTipOpened
Event Type
Type
System.EventHandler<ComboBoxToolTipOpenedEventArgs>

ToolTipOpening

Occurs while showing the tooltip for the control.

Declaration
public event EventHandler<ComboBoxToolTipOpeningEventArgs> ToolTipOpening
Event Type
Type
System.EventHandler<ComboBoxToolTipOpeningEventArgs>

Implements

System.IDisposable
System.ComponentModel.ISupportInitialize