SwiftUI Academy · 课时

插入、更新与删除

修改存储并实时反映变化。

第 4 / 4 课13 个步骤

插入、更新与删除 是 CoddyKit 上的免费 SwiftUI Academy 课时。这是第 4 节课，共 4 节。你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。这是 SwiftUI Academy 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 SwiftUI Academy 课程共包含 4 节课。

本课时的部分内容尚未翻译，以英文显示。

Changing Your Data

Now you will change the store: add new records, edit existing ones, and remove what you no longer need. ✏️

Inserting a Record

Create an object and call insert on the context to add it. SwiftData starts tracking it for saving right away.

let task = Task(title: "Walk dog")
context.insert(task)

Insert Then Appears

After an insert, any @Query view shows the new row at once. You do not refresh the list yourself.

Updating a Property

To edit a record, just change its property on the tracked object. SwiftData notices and saves the new value.

task.isDone = true

No Special Edit Call

There is no separate update method. Because the object is tracked, direct assignment is the whole update flow.

task.title = "Walk the dog twice"

Deleting a Record

Remove an object with delete on the context. It disappears from the store and from every query view.

context.delete(task)

Deleting from a List

Wire up swipe-to-delete with onDelete, then call delete for each index. Users remove rows with a familiar gesture.

.onDelete { offsets in
    for i in offsets {
        context.delete(tasks[i])
    }
}

Saving the Changes

SwiftData autosaves, but you can call save to commit immediately. It is wise before the app might close.

try context.save()

Batch Operations

Loop over a set of objects to insert or delete many at once. The context batches the work efficiently for you.

for t in finished {
    context.delete(t)
}

Handling Errors

Wrap a manual save in do-catch so a failure does not crash your app. You can warn the user instead.

do { try context.save() }
catch { print(error) }

Changes Flow to the UI

Every insert, edit, and delete reflects live in your views. The store and screen stay perfectly in step.

Quick Check

Quick check on editing data.

在交互式课程中回答

Recap: Editing Data

You can now insert, edit by assignment, and delete records, with the UI updating live. You have full control over your SwiftData store. 🚀

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常见问题解答

「插入、更新与删除」课时是免费的吗？

是的 — 「插入、更新与删除」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 SwiftUI Academy 课程的其余内容，请升级到 CoddyKit PRO。 SwiftUI Academy 课程共包含 4 节课。

「插入、更新与删除」这节课中我会学到什么？

修改存储并实时反映变化。你通过在浏览器中直接运行的动手代码来练习 SwiftUI Academy，全天候 AI 导师会在你学习这节课的过程中回答你的问题。

学习 SwiftUI Academy 需要有经验吗？

无需任何先前经验。CoddyKit 上的 SwiftUI Academy 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。这是第 4 节课，共 4 节。

「插入、更新与删除」课时需要多长时间？

大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。

我能在这节 SwiftUI Academy 课中编写并运行代码吗？

能。每节 SwiftUI Academy 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。

此课程中的所有课时

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