If a file is selected, then run the custom function; otherwise, do nothing.

如果选择了文件，则运行定制函数；否则，不进行任何操作。

youdao

Appendix B shows sample code for a custom Function Selector.

附录B显示了一个自定义函数选择器的示例代码。

youdao

If needed, implement a custom Function Selector.

如果需要，请实现一个自定义函数选择器。

youdao

Each unit is custom-built to ensure superb form and function.

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Top-mounted exposure compensation and mode dials are strategically placed for simple access and operation, while custom function and AEL buttons on the back panel are also easily accessible.

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