1. First, Understand Two “Areas”: Working Directory and Staging Area¶
Imagine Git’s workflow as a “small factory” for “file preparation and submission”:
- Working Directory: Like “scrap paper” on your desk—this is where all code modifications happen. For example, when you open a local project folder and edit files like index.html or app.js, these changes are made in the working directory.
- Staging Area: Like a “package waiting for review”—you “package” modified files from the working directory into this area. The staging area temporarily stores version information of these files, allowing you to choose whether to finally commit them to the repository.
2. Working Directory vs. Staging Area: What Are the Core Differences?¶
| Comparison Item | Working Directory | Staging Area |
|---|---|---|
| Location | Local file system (the folder you can directly see/operate on) | Internal “intermediate repository” in Git (hidden in the Git system, viewable only via commands) |
| Direct Editing | You can directly modify or delete files (e.g., changing code in app.js) |
You cannot directly edit! Only modify via commands like git add or git reset |
| Git Tracking | Not tracked by Git (unless you run git add or git init) |
Marked by Git as “to be committed” (only changes after git add will be recorded in commit) |
| Visibility of Changes | All changes are directly visible (e.g., you can see content changes you made) | Changes are only visible to Git; you cannot view specific files directly (check staging status via git status) |
3. Why Must You “Add Before Commit”?¶
Suppose you have two tasks: writing a weekly report (A.txt) and a plan (B.txt), but you only want to submit the report first—the plan is still incomplete. If you skip the “staging area” and directly commit, Git will submit both A and B, causing the incomplete plan (B.txt) to be mistakenly committed.
The staging area enables “selective submission”:
- If you directly run commit, Git can only see all changes in the working directory and cannot distinguish between “what to commit” and “what to keep as drafts.”
- git add acts like “packaging”: you can specify which files to “put” into the staging area (e.g., git add A.txt), while leaving other files (like B.txt) in the working directory for further editing. When you finally commit, only the staged content (A.txt) will be submitted.
4. Simple Command Demo Workflow¶
- Modify in the Working Directory: Edit both
A.txtandB.txtin your local project (e.g., A.txt has the weekly report, B.txt is a draft plan). - Check Status: Run
git status—both A.txt and B.txt will show as “modified” (indicating updates in the working directory, but nothing in the staging area yet). - Add to Staging Area: To submit only A.txt, run
git add A.txt. - Commit to Repository: Run
git commit -m "Submit weekly report". Only the changes in A.txt will be recorded in the local repository; the draft B.txt remains in the working directory and will not be committed.
5. Summary: The Staging Area is a “Buffer,” and Commit is a “Snapshot”¶
- Working Directory: The “editing” space—changes can be easily reverted (e.g., undoing file modifications).
- Staging Area: The “pre-commit buffer”—allows you to select the scope of content to commit.
- Repository: The “final storage”—
commitpermanently records the content of the staging area.
The essence of “add before commit” is to let you submit modifications selectively and in stages, avoiding accidental commits of incomplete drafts or unnecessary content.
After this understanding, does Git’s staging area and working directory seem like “scrap paper and a to-do list”? Mastering this mechanism will make code submission more flexible and controllable!