can
Returns whether the font style of the given block can be toggled between italic and normal.
Parameters
the text block block whose font style should be toggled.
the start index of the range whose text case should be changed. If the value is negative and the block is currently being edited, this will fall back to the start of the current cursor index / selected range. If the value is negative and the block is not being edited, this will fall back to the start of the entire text range.
the index after the last character whose text case should be changed. If the value is negative and the block is currently being edited, this will fall back to the end of the current cursor index / selected range. If the value is negative and the block is not being edited, this will fall back to the end of the entire text range.