总结：

• git add -a 所有的更改操作--新建，更改，删除；
• git add . 只包括 新建 ，修改操作；无删除；
• git add -u 只包括修改，删除操作，无新建；

示例：

git initecho Change me > change-meecho Delete me > delete-megit add change-me delete-megit commit -m initialecho OK >> change-merm delete-meecho Add me > add-megit status# Changed but not updated:#   modified:   change-me#   deleted:    delete-me# Untracked files:#   add-megit add .git status# Changes to be committed:#   new file:   add-me#   modified:   change-me# Changed but not updated:#   deleted:    delete-megit resetgit add -ugit status# Changes to be committed:#   modified:   change-me#   deleted:    delete-me# Untracked files:#   add-megit resetgit add -Agit status# Changes to be committed:#   new file:   add-me#   modified:   change-me#   deleted:    delete-me

Summary:

• git add -Astages All
• git add .stages new and modified, without deleted
• git add -ustages modified and deleted, without new

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