# Commands You can perform editing operations on the mathfield programmatically. For example, to insert a fraction when the user clicks a button. You can do this by dispatching **commands** to the mathfield, such as `"select-all"`, `"move-to-next-char"`, `"delete-backward"`, etc... **To dispatch commands** use the [`mf.executeCommand()`](/docs/mathfield/#(%22mathfield-element%22%3Amodule).(MathfieldElement%3Aclass).(executeCommand%3Ainstance)) method. ```js mf.executeCommand("delete-backward"); ``` **To associate commands with virtual keyboard keycaps** use the `command` property of the keycap definition. For example: ```json example { "class": "action", "label": "Delete", "command": 'perform-with-feedback("delete-backward")' } ``` Commands are identified by a string called the **selector**. The selector can use either CamelCase or kebab-case syntax. For example: `"moveToNextChar"` or `"move-to-next-char"` are the same selector. Most commands take no parameters. When a command does have a parameter, a tuple with the selector and the commands arguments can be passed to `executeCommand()`. For example: ```js mf.executeCommand(["insert", "(#0)"]); ``` The command above will insert an open and close parenthesis around the selection (the `#0` sequence is replaced with the current selection). ## Editing Commands - `insert` This selector takes two arguments. The first one is required and is the content to be inserted, as a string. The second one is an optional set of key value pairs: - `insertionMode`: one of `"replaceSelection"`, `"replaceAll"`, `"insertBefore"` or `"insertAfter"`. - `selectionMode`: one of `"placeholder"` (the selection will be the first available placeholder in the item that has been inserted), `"after"` (the selection will be an insertion point after the item that has been inserted), `"before"` (the selection will be an insertion point before the item that has been inserted) or `"item"` (the item that was inserted will be selected). - `delete` Synonym for `deleteNextChar` - `deleteBackward` `deleteForward` - `deleteNextWord` `deletePreviousWord` - `deleteToGroupStart` `deleteToGroupEnd` - `deleteToMathFieldEnd` - `deleteAll` - `transpose` ## Edit Menu - `undo` - `redo` - `cutToClipboard` - `copyToClipboard` - `pasteFromClipboard` ## User Interface - `commit` The user has completed input. Triggered when pressing the RETURN or ENTER key. - `switchMode` - `complete` Exit command mode and insert result - `nextSuggestion` and `previousSuggestion` when the popover panel is selected, display the next/previous suggestion - `toggleKeystrokeCaption` Show/hide the keystroke caption panel. This panel displays the keys being typed, including the shortcuts. Great for demos! - `toggleVirtualKeyboard` Show/hide the virtual keyboard ## Scrolling - `scrollToStart` - `scrollToEnd` - `scrollIntoView` ## Navigating - `moveToNextChar` `moveToPreviousChar` - `moveToNextPlaceholder` `moveToPreviousPlaceholder` - `moveToNextWord` `moveToPreviousWord` - `moveToGroupStart` `moveToGroupEnd` - `moveToMathfieldStart` `moveToMathfieldEnd` - `moveUp` `moveDown` - `moveToSuperscript` `moveToSubscript` - `moveToOpposite` - `moveBeforeParent` `moveAfterParent` ## Extending the Selection - `selectGroup` - `selectAll` - `extendToNextChar` `extendToPreviousChar` - `extendToNextWord` `extendToPreviousWord` - `extendUp` `extendDown` - `extendToNextBoundary` `extendToPreviousBoundary` - `extendToGroupStart` `extendToGroupEnd` - `extendToMathFieldStart` `extendToMathFieldEnd` ## Arrays - `addRowAfter` `addRowBefore` - `addColumnAfter` `addColumnBefore` - `removeRow` `removeColumn` ## Speech - `speak` This selector takes an optional argument, the string that determines what should be spoken. The valid values are: - `all` - `left` - `right` - `selection` - `parent` - `group` The second parameter determines whether what is being spoken should be highlighted. It is an object: `{withHighlighting: boolean}` (default is false). Note: highlighting currently only works when using Amazon's AWS speech synthesizer.