TermEdit

Inheritance Hierarchy

          IComponent

          IControl

          ICustomEdit

          ITermEdit

          TermEdit

Description

The TermEdit component is an editor of expressions made using terms.

Working with the Component

This component is used to make equations using terms. A term is a text element containing a link to an object. When an equation is created, the component editing area displays text notifications specified in the Text property of each term. Calculations use the internal term representation specified in the Formula property of each term. It is possible to set up character color including using a term as a hyperlink. Term properties and methods are used for that: CustomHyperlinkStyle, Color, SetTextColor.

The common expression displayed in the component is determined by the Text property, and the expression that is used to execute calculations (expression based on the terms internal representations (formulas) is determined by the Formula property.

To create an expression, create a terms collection available in the Terms property. An expression is formed by inserting the required terms at the specific positions. Terms are inserted using the PutCustom, PutLiteral and PutTerm methods.

To manage the expression direct input possibility, use the DirectInput property. When an expression is input manually, the text is automatically converted into terms.

NOTE. The TermEdit component and the TermEditEx component differ in their internal implementation.

Properties of the TermEdit Component

  Property name Brief description
The Align property determines behavior of the component when its parent component is resized.
The AllowDrag property determines whether an object can be dragged from the component.
The AllowDrop property determines whether the component can accept a dragged object.
The Anchors property returns settings that determine the percentage of the size change for the current component when the parent component is resized.
The AutoReparsing property determines whether the text should be automatically transformed into terms and operands.
The AutoSelect property determines whether component text is selected when the component gets focused.
The BorderStyle property determines a component border style.
The Brush property determines the brush that is used to fill component area.
The CanUndo property returns True if it is possible to undo text changes in the component.
The CharacterCasing property determines the case of the entered characters.
The ClientHeight property is used to receive or specify the height of the component’s client area.
The ClientWidth property is used to receive or specify the width of the component’s client area.
The Color property determines a component background color.
The ComponentCount property returns the number of child components.
The Components property returns the child component.
The Cursor property determines the look of the cursor over the component.
The Data property is used to store any custom data.
The DirectInput property determines whether direct input is possible.
The Enabled property determines whether the component is available for the user.
The EnableHyperlinks property determines whether it is possible to display a term as a hyperlink.
The Focused property returns True if the focus is set on the component.
The Font property determines the set of characteristics describing the font that is used to display text.
The Formula property determines a term formula.
The Height property determines component height.
The HelpContext property determines a unique index for the context help section for this component.
The HideSelection property determines whether the selected component text remains the same when the focus moves to another component.
The Hint property determines a component tooltip text.
The Hyperlink property determines whether the expression, the index of which is an input parameter, is a hyperlink.
The Left property determines the coordinate of the left border of the component.
The MaxLength property determines the maximum length of the entered text.
The Modified property returns True if the component text has been changed.
The Name property determines a component name.
The Parent property determines a parent component.
The ParentColor property determines whether the component inherits the color of the parent component.
The ParentFont property determines whether the component uses the font of the parent component.
The ParentShowHint property determines whether a tooltip is displayed.
The PopupMenu property determines the context menu to be displayed on right-click on the component.
The ReadOnly property determines whether the user can change component text.
The Scrolls property returns parameters of component's scrollbars.
The SelLength property determines the number of characters selected in the component text.
The SelStart property determines the cursor position, from which to start text selection in the component.
The SelText property determines the text selected in the component.
The ShowHint property enables and disables showing a component tooltip.
The TabOrder property determines the component position in the tab order.
The TabStop property determines whether the component is focused when the TAB key is pressed.
The Tag property is not used by the compiler. The user can change the value of the Tag property and use it as he wishes.
The Terms property returns the terms collection.
The Text property determines the row identifying a component for the user.
The Top property determines the coordinate of the top border of the component.
The Visible property determines visibility of the component during execution.
The WantReturns property determines whether a carriage return symbol can be inserted into the edited text.
The WantTabs property determines whether a tab symbol can be inserted into the edited text.
The Width property determines component width.
The WordWarp property determines whether the lines exceeding component length are wrapped to a new line.

Methods of the TermEdit Component

  Method name Brief description
The BeginUpdate method disables a set of internal mechanisms for accelerating insertion of terms into the component.
The BringToFront method brings a component to front.
The Clear method deletes all text in the component.
The ClearSelection method deletes all text selected in the component.
The ClearUndo method is used to fix the changes of the Text property.
The ClientToScreen method converts the coordinates of a point specified relative to the component coordinate system into screen coordinates.
The CopyToClipboard method enables the user to copy selected data to the clipboard.
The CutToClipboard method enables the user to cut selected data and place it to the clipboard.
The DoDragDrop method enables to start dragging operation.
The EndUpdate method restores work of internal mechanisms of the component, which were disabled for acceleration of insertion of terms into the component.
The GetImage method returns the image of the component with all the child components.
The PasteFromClipboard method pastes data from the clipboard.
The PutCustom method enables the user to place the custom term into the specified position.
The PutLiteral method enables the user to place the literal term into the specified position.
The PutTerm method enables the user to place the term into the specified position.
The Reparse method transforms editor text and redistributes terms in the component.
The ScreenToClient method converts screen coordinates of a point into coordinates specified relative to the component coordinate system.
The SelectAll method selects component text.
The SetFocus method sets focus to this component.
The SendToBack method sends a component to back.
The Undo method undoes the last text change in the component.

Events of the TermEdit Component

  Event name Brief description
The OnBeginDrag event occurs for a component when the user starts to drag an object from the component.
The OnChange event occurs after changing the Text property of the editing component.
The OnClick event occurs if the user clicks the component area with the main mouse button.
The OnDblClick event occurs if the user double-clicks a component area with the mouse button.
The OnDragDrop event occurs for the component if the user drops a dragged object over it.
The OnDragEnter event occurs when a dragged object crosses the borders of this component.
The OnDragLeave event occurs when a dragged object leaves the borders of this component.
The OnDragOver event occurs for the component when the user drags an object over it.
The OnEnter event occurs when the component receives focus.
The OnExit event occurs when the component loses focus.
The OnHScroll event occurs when horizontal scrollbar slider changes its position.
The OnHyperlink event occurs on clicking on the term hyperlink.
The OnKeyDown event occurs if the component is focused and the keyboard key is pressed.
The OnKeyPress event occurs if the component is focused when the user presses a character key.
The OnKeyUp event occurs if the component is focused and the user releases any button previously pressed.
The OnMouseDown event occurs if the pointer is in component's area and a mouse key is pressed.
The OnMouseEnter event occurs when mouse cursor enters the component area.
The OnMouseHover event occurs when mouse cursor is held in the component area.
The OnMouseLeave event occurs when mouse cursor leaves the component area.
The OnMouseMove event occurs on moving the cursor over component.
The OnMouseUp event occurs on releasing mouse button when the cursor is in component area.
The OnMouseWheel event occurs if the component is focused when the mouse wheel is rotated.
The OnParseTerm event occurs when the editor text is transformed into terms and operands.
The OnVScroll event occurs when vertical scrollbar slider changes its position.

See also:

Additional Components