Represents the command used to drag and fill a range on the sheet.
* The command has a boolean field canUndo that indicates whether the command supports undo and redo operation, and a method execute that performs an execute operation or undo operation.
* The arguments of the execute method are as follows.
context {GC.Spread.Sheets.Workbook} The context of the operation.
options {Object} The options of the operation.
* options.sheetName {string} The sheet name.
* options.startRange {GC.Spread.Sheets.Range} The start range.
* options.fillRange {GC.Spread.Sheets.Range} The fill range.
* options.autoFillType {GC.Spread.Sheets.Fill.AutoFillType} The auto fill type.
* options.fillDirection {GC.Spread.Sheets.Fill.FillDirection} The fill direction.
isUndo {boolean} true if an undo operation; otherwise, false.