您不能在iOS 13之前的iOS版本中本地使用SFSymbols(请参阅Apple的

You can not use SFSymbols natively in iOS versions older than iOS 13 (see Apple's Human Interface Guidelines for SF Symbols).

但是，如果您对使用图形感兴趣，可以使用 SFSymbols应用导出图标的SVG版本.然后使用一些图形工具将它们转换为PNG图标，您可以将其导入到资产目录中.

However, if you are interested in using the graphics you can use the SFSymbols app to export SVG versions of the icon. Then use some graphics tool to convert them to PNG icons you can import into your asset catalog.