首先，用XCode打开

/Applications/Xcode.app/Contents/Frameworks/IDEKit.framework/Resources/IDETextKeyBindingSet.plist

增加

<key>My Custom Keys</key>
<dict>
    <key>Move Line Up</key>
    <string>selectLine:, cut:, moveUp:, moveToBeginningOfLine:, paste:, moveUp:</string>
    <key>Move Line Down</key>
    <string>selectLine:, cut:, moveDown:, moveToBeginningOfLine:, paste:, moveUp:</string>
    <key>Duplicate Line</key>
    <string>moveToBeginningOfLine:, deleteToEndOfLine:, yank:, insertNewline:, moveToBeginningOfLine:, yank:</string>
    <key>Delete Line</key>
    <string>selectLine:, delete:</string>
</dict>

进入xcode，Command+, 打开快捷键设置，搜索刚刚设置的key名称，输入你想设置的快捷键即可。