新建一个叫sublime.reg的文件，里面的内容如下：
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT*\shell\SublimeText3]
@="open with SublimeText3 "
"Icon"="C:\Program Files\Sublime Text 3\sublime_text.exe,0"
[HKEY_CLASSES_ROOT*\shell\SublimeText3\command]
@="C:\Program Files\Sublime Text 3\sublime_text.exe %1"
[HKEY_CLASSES_ROOT\Directory\shell\SublimeText3]
@="open with SublimeText3 "
"Icon"="C:\Program Files\Sublime Text 3\sublime_text.exe,0"
[HKEY_CLASSES_ROOT\Directory\shell\SublimeText3\command]
@="C:\Program Files\Sublime Text 3\sublime_text.exe %1"
保存后运行即可。