What is the method for incorporating both single selection and range selection in an application?

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One method for incorporating both single selection and range selection in an application is to provide users with two different modes of selection.

In single selection mode, the user can select only one item at a time by clicking on it. In range selection mode, the user can select a range of items by clicking and dragging the mouse over them.

To switch between modes, the application can provide a toggle button or keyboard shortcut that enables the user to switch between single and range selection modes.

Additionally, the application can provide visual feedback to indicate which mode is currently active, so the user is always aware of the current selection mode.