RepositoryItemTextEdit.AllowNullInput Property

Gets or sets whether end-users can reset the editor’s value to null via keyboard. The edit value is reset to Color.Empty for the ColorEdit and ColorPickEdit controls.

Namespace: DevExpress.XtraEditors.Repository

Assembly: DevExpress.XtraEditors.v19.1.dll

Declaration

C#

[DXCategory("Behavior")]
[DefaultValue(DefaultBoolean.Default)]
public virtual DefaultBoolean AllowNullInput { get; set; }

VB.NET

<DXCategory("Behavior")>
<DefaultValue(DefaultBoolean.Default)>
Public Overridable Property AllowNullInput As DefaultBoolean

Property Value

Type	Default	Description
DefaultBoolean	**Default**	A DefaultBoolean value that specifies if end-users can set the editor’s value to a null reference.

Available values:

Name	Description
True	Corresponds to a Boolean value of true.
False	Corresponds to a Boolean value of false.
Default	The value is determined by the current object’s parent object setting (e.g., a control setting).

Remarks

If the AllowNullInput property is set to DefaultBoolean.True, end-users can reset the editor’s value using the actions shown below.

Editors	Action	Result
All editors except ColorEdit and ColorPickEdit.	Press CTRL+DEL or CTRL+0.	The edit value is set to null (Nothing in Visual Basic).
ColorEdit and ColorPickEdit.	Press CTRL+DEL or CTRL+0.	The edit value is set to Color.Empty.
Editors with the built-in auto-search functionality (PopupBaseAutoSearchEdit descendants, which include ComboBoxEdit, LookUpEdit, MRUEdit, etc.)	Clear the text. Note: Set the RepositoryItemButtonEdit.TextEditStyle setting to Standard to allow text edit operations).	The edit value is set to null (Nothing in Visual Basic).

If the AllowNullInput property is set to False, these actions are disabled.

The DefaultBoolean.Default value is treated differently for different editors, as covered in the table below:

Editors	DefaultBoolean.Default is interpreted as
DateEdit (standalone and inplace)	True
Standalone editors	False
Inplace editors embedded in grid and tree list control cells.	True
Inplace editors embedded in bars and Ribbon UI.	False

For the DateEdit control, the AllowNullInput and RepositoryItemDateEdit.ShowClear properties are synchronized. When you set the ShowClear property to true, the AllowNullInput property is set to Default, and vice versa. When you set the ShowClear property to false, the AllowNullInput property is set to False, and vice versa.

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the AllowNullInput property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

Reporting_how-to-create-parameter-editors-that-are-dependent-on-each-others-values-e3291/CS/DependentEditors/XtraReportBase.cs#L71

DateEdit startDateEdit = (DateEdit)FindEditor(parametersInfo, startDateParameterName);
startDateEdit.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.False;
DateEdit endDateEdit = (DateEdit)FindEditor(parametersInfo, endDateParameterName);

XPO_how-to-adjust-the-lookupedit-so-it-can-be-used-with-persistent-objects-e570/CS/Form1.cs#L150

lookUpEdit.Properties.DataSource = new XPCollection<ProjectStatus>(unitOfWork1);
lookUpEdit.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.True;

how-to-implement-incremental-search-for-an-edit-form-via-the-lookupedit-e707/CS/Form1.cs#L296

lookUpEdit1.Properties.NullText = "[Type a contact to find]";
lookUpEdit1.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.True;
lookUpEdit1.Properties.TextEditStyle = TextEditStyles.Standard;

objectdatasource-how-to-provide-a-custom-parameter-editor-t246429/CS/CustomRepositoryItem/MyRepositoryItemsProvider.cs#L40

lookUpEdit.NullText = Resources.MyRepositoryItemsProvider_GetRepositoryItem_Nobody;
lookUpEdit.AllowNullInput = DefaultBoolean.True;

how-to-synchronize-event-colors-with-scheduler-labels/CS/SchedulerGSync/SchedulerGSync/SyncOptionsForm.cs#L16

this.lookUpEdit1.Properties.NullValuePromptShowForEmptyValue = false;
this.lookUpEdit1.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.False;
this.lookUpEdit1.Properties.NullText = String.Empty;

VB.NET

Reporting_how-to-create-parameter-editors-that-are-dependent-on-each-others-values-e3291/VB/DependentEditors/XtraReportBase.vb#L92

Dim startDateEdit As DateEdit = CType(FindEditor(parametersInfo, startDateParameterName), DateEdit)
startDateEdit.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.False
Dim endDateEdit As DateEdit = CType(FindEditor(parametersInfo, endDateParameterName), DateEdit)

XPO_how-to-adjust-the-lookupedit-so-it-can-be-used-with-persistent-objects-e570/VB/Form1.vb#L152

lookUpEdit.Properties.DataSource = New XPCollection(Of ProjectStatus)(unitOfWork1)
lookUpEdit.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.True

how-to-implement-incremental-search-for-an-edit-form-via-the-lookupedit-e707/VB/Form1.vb#L281

lookUpEdit1.Properties.NullText = "[Type a contact to find]"
lookUpEdit1.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.True
lookUpEdit1.Properties.TextEditStyle = TextEditStyles.Standard

objectdatasource-how-to-provide-a-custom-parameter-editor-t246429/VB/CustomRepositoryItem/MyRepositoryItemsProvider.vb#L55

lookUpEdit.NullText = My.Resources.MyRepositoryItemsProvider_GetRepositoryItem_Nobody
lookUpEdit.AllowNullInput = DefaultBoolean.True

how-to-synchronize-event-colors-with-scheduler-labels/VB/SchedulerGSync/SchedulerGSync/SyncOptionsForm.vb#L19

Me.lookUpEdit1.Properties.NullValuePromptShowForEmptyValue = False
Me.lookUpEdit1.Properties.AllowNullInput = DevExpress.Utils.DefaultBoolean.False
Me.lookUpEdit1.Properties.NullText = String.Empty