From 5e40d13bcde36ab730b48e0a8cca29b18ec95242 Mon Sep 17 00:00:00 2001 From: David McCabe Date: Wed, 25 Oct 2023 10:40:39 -0700 Subject: [PATCH 1/3] Add useFormState reference (#6338) Add useFormState reference --- .../reference/react-dom/hooks/useFormState.md | 291 ++++++++++++++++++ src/sidebarReference.json | 5 + 2 files changed, 296 insertions(+) create mode 100644 src/content/reference/react-dom/hooks/useFormState.md diff --git a/src/content/reference/react-dom/hooks/useFormState.md b/src/content/reference/react-dom/hooks/useFormState.md new file mode 100644 index 0000000000..ca7af25361 --- /dev/null +++ b/src/content/reference/react-dom/hooks/useFormState.md @@ -0,0 +1,291 @@ +--- +title: useFormState +canary: true +--- + + + +The `useFormState` Hook is currently only available in React's canary and experimental channels. Learn more about [React's release channels here](/community/versioning-policy#all-release-channels). In addition, you need to use a framework that supports React Server Components to get the full benefit of `useFormState`. + + + + + +`useFormState` is a Hook that allows you to read the return value of the form action after a form is submitted. + +```js +const [state, formAction] = useFormState(action, initalState); +``` + + + + + +--- + +## Reference {/*reference*/} + +### `useFormState()` {/*useformstate*/} + +In the context of React Server Components, an *action* is a function that may be [executed when a form is submitted](/reference/react-dom/components/form). You can execute actions on the server or on the client. + +{/* TODO T164397693: link to actions documentation once it exists */} + +Call `useFormState` at the top level of your component to see the return value of an action after submitting a form. You pass `useFormState` an existing action as well as an initial state, and it returns a new action that you use when submitting your form, along with the latest form state. + +```js +function AddToCart({itemID}) { + const [message, formAction] = useFormState(addToCartAction, null); + return ( +
+ +
+ {message} + + ); +} + +export default function App() { + return ( + <> + + + + ) +} +``` + +```js actions.js +"use server"; + +export async function addToCart(prevState, queryData) { + const itemID = queryData.get('itemID'); + if (itemID === "1") { + return "Added to cart"; + } else { + return "Couldn't add to cart: the item is sold out."; + } +} +``` + +```css styles.css hidden +form { + border: solid 1px black; + margin-bottom: 24px; + padding: 12px +} + +form button { + margin-right: 12px; +} +``` + +```json package.json hidden +{ + "dependencies": { + "react": "experimental", + "react-dom": "experimental", + "react-scripts": "^5.0.0" + }, + "main": "/index.js", + "devDependencies": {} +} +``` + + + + +#### Display structured information after submitting a form {/*display-structured-information-after-submitting-a-form*/} + +The return value from a server action can be any serializable value. For example, it could be an object that includes a boolean indicating whether the action was successful, an error message, or updated information. + + + +```js App.js +import { useState } from "react"; +import { useFormState } from "react-dom"; +import { addToCart } from "./actions.js"; + +function AddToCartForm({itemID, itemTitle}) { + const [formState, formAction] = useFormState(addToCart, {}); + return ( +
+

{itemTitle}

+ + + {formState?.success && +
+ Added to cart! Your cart now has {formState.cartSize} items. +
+ } + {formState?.success === false && +
+ Failed to add to cart: {formState.message} +
+ } +
+ ); +} + +export default function App() { + return ( + <> + + + + ) +} +``` + +```js actions.js +"use server"; + +export async function addToCart(prevState, queryData) { + const itemID = queryData.get('itemID'); + if (itemID === "1") { + return { + success: true, + cartSize: 12, + }; + } else { + return { + success: false, + message: "The item is sold out.", + }; + } +} +``` + +```css styles.css hidden +form { + border: solid 1px black; + margin-bottom: 24px; + padding: 12px +} + +form button { + margin-right: 12px; +} +``` + +```json package.json hidden +{ + "dependencies": { + "react": "experimental", + "react-dom": "experimental", + "react-scripts": "^5.0.0" + }, + "main": "/index.js", + "devDependencies": {} +} +``` + + + + + + +## Troubleshooting {/*troubleshooting*/} + +### My action can no longer read the submitted form data {/*my-action-can-no-longer-read-the-submitted-form-data*/} + +When you wrap an action with `useFormState`, it gets an extra argument *as its first argument*. The submitted form data is therefore its *second* argument instead of its first as it would usually be. The new first argument that gets added is the current state of the form. + +```js +function action(currentState, formData) { + // ... +} +``` diff --git a/src/sidebarReference.json b/src/sidebarReference.json index acc93328ac..33afbf89ea 100644 --- a/src/sidebarReference.json +++ b/src/sidebarReference.json @@ -166,6 +166,11 @@ "title": "Hooks", "path": "/reference/react-dom/hooks", "routes": [ + { + "title": "useFormState", + "path": "/reference/react-dom/hooks/useFormState", + "canary": true + }, { "title": "useFormStatus", "path": "/reference/react-dom/hooks/useFormStatus", From 6ef844b906a42cb9d70a5de15941dfce123e8f7d Mon Sep 17 00:00:00 2001 From: David McCabe Date: Wed, 25 Oct 2023 13:18:47 -0700 Subject: [PATCH 2/3] useFormState reference fixes (#6383) * Add useFormState reference * Matt's suggestions for useFormState reference * Incorporated PR feedback for useFormState --- .../reference/react-dom/hooks/index.md | 5 +- .../reference/react-dom/hooks/useFormState.md | 62 +++++++++---------- 2 files changed, 34 insertions(+), 33 deletions(-) diff --git a/src/content/reference/react-dom/hooks/index.md b/src/content/reference/react-dom/hooks/index.md index 6490dc1113..937de808c1 100644 --- a/src/content/reference/react-dom/hooks/index.md +++ b/src/content/reference/react-dom/hooks/index.md @@ -1,5 +1,5 @@ --- -title: "React DOM Hooks" +title: "Built-in React DOM Hooks" --- @@ -21,7 +21,7 @@ Form Hooks are currently only available in React's canary and experimental chann *Forms* let you create interactive controls for submitting information. To manage forms in your components, use one of these Hooks: * [`useFormStatus`](/reference/react-dom/hooks/useFormStatus) allows you to make updates to the UI based on the status of the a form. -* `useFormState` allows you to manage state inside a form. +* [`useFormState`](/reference/react-dom/hooks/useFormState) allows you to manage state inside a form. ```js function Form({ action }) { @@ -46,3 +46,4 @@ function Button() { ); } ``` + diff --git a/src/content/reference/react-dom/hooks/useFormState.md b/src/content/reference/react-dom/hooks/useFormState.md index ca7af25361..53c73ae387 100644 --- a/src/content/reference/react-dom/hooks/useFormState.md +++ b/src/content/reference/react-dom/hooks/useFormState.md @@ -5,16 +5,16 @@ canary: true -The `useFormState` Hook is currently only available in React's canary and experimental channels. Learn more about [React's release channels here](/community/versioning-policy#all-release-channels). In addition, you need to use a framework that supports React Server Components to get the full benefit of `useFormState`. +The `useFormState` Hook is currently only available in React's canary and experimental channels. Learn more about [release channels here](/community/versioning-policy#all-release-channels). In addition, you need to use a framework that supports [React Server Components](/reference/react/use-client) to get the full benefit of `useFormState`. -`useFormState` is a Hook that allows you to read the return value of the form action after a form is submitted. +`useFormState` is a Hook that allows you to update state based on the result of a form action. ```js -const [state, formAction] = useFormState(action, initalState); +const [state, formAction] = useFormState(fn, initialState); ``` @@ -25,24 +25,25 @@ const [state, formAction] = useFormState(action, initalState); ## Reference {/*reference*/} -### `useFormState()` {/*useformstate*/} - -In the context of React Server Components, an *action* is a function that may be [executed when a form is submitted](/reference/react-dom/components/form). You can execute actions on the server or on the client. +### `useFormState(action, initialState)` {/*useformstate*/} {/* TODO T164397693: link to actions documentation once it exists */} -Call `useFormState` at the top level of your component to see the return value of an action after submitting a form. You pass `useFormState` an existing action as well as an initial state, and it returns a new action that you use when submitting your form, along with the latest form state. +Call `useFormState` at the top level of your component to create component state that is updated [when a form action is invoked](/reference/react-dom/components/form). You pass `useFormState` an existing form action function as well as an initial state, and it returns a new action that you use in your form, along with the latest form state. The latest form state is also passed to the function that you provided. ```js -function AddToCart({itemID}) { - const [message, formAction] = useFormState(addToCartAction, null); +import { useFormState } from "react-dom"; + +async function increment(previousState, formData) { + return previousState + 1; +} + +function StatefulForm({}) { + const [state, formAction] = useFormState(increment, 0); return ( -
- -
) } @@ -56,23 +57,22 @@ If used with a server action, `useFormState` allows the server's response from s #### Parameters {/*parameters*/} -* `action`: The action to be performed when the form is submitted. When the action is called, it will receive the previous state of the form (initially the `initialState` that you pass, subsequently its previous return value) as its initial argument, followed by the arguments that an action normally receives. -* `initialState`: The value you want the state to be initially. It can be any serializable value. This argument is ignored after the form is first submitted. +* `fn`: The function to be called when the form is submitted or button pressed. When the function is called, it will receive the previous state of the form (initially the `initialState` that you pass, subsequently its previous return value) as its initial argument, followed by the arguments that a form action normally receives. +* `initialState`: The value you want the state to be initially. It can be any serializable value. This argument is ignored after the action is first invoked. {/* TODO T164397693: link to serializable values docs once it exists */} - #### Returns {/*returns*/} `useFormState` returns an array with exactly two values: -1. The current state. During the first render, it will match the `initialState` you have passed. After the form is submitted, it will match the value returned by the action. -2. A new action that you can pass as the `action` prop to your `form` component. +1. The current state. During the first render, it will match the `initialState` you have passed. After the action is invoked, it will match the value returned by the action. +2. A new action that you can pass as the `action` prop to your `form` component or `formAction` prop to any `button` component within the form. #### Caveats {/*caveats*/} -* When used with a framework that supports React Server Components, `useFormState` lets you make forms interactive before JavaScript has executed on the client. When used without Server Components, there is no advantage to using it over component local state. -* The action passed to `useFormState` receives an extra argument, the previous or initial state state, as its first argument. This makes its signature different than if it were used directly without `useFormState`. +* When used with a framework that supports React Server Components, `useFormState` lets you make forms interactive before JavaScript has executed on the client. When used without Server Components, it is equivalent to component local state. +* The function passed to `useFormState` receives an extra argument, the previous or initial state, as its first argument. This makes its signature different than if it were used directly as a form action without using `useFormState`. --- @@ -102,7 +102,7 @@ function MyComponent() { 1. The current state of the form, which is initially set to the initial state you provided, and after the form is submitted is set to the return value of the action you provided. 2. A new action that you pass to `
` as its `action` prop. -When the form is submitted, the action that you provided will be called. Its return value will become the new current state of the form. +When the form is submitted, the action function that you provided will be called. Its return value will become the new current state of the form. The action that you provide will also receive a new first argument, namely the current state of the form. The first time the form is submitted, this will be the initial state you provided, while with subsequent submissions, it will be the return value from the last time the action was called. The rest of the arguments are the same as if `useFormState` had not been used @@ -141,8 +141,8 @@ function AddToCartForm({itemID, itemTitle}) { export default function App() { return ( <> - - + + ) } @@ -176,8 +176,8 @@ form button { ```json package.json hidden { "dependencies": { - "react": "experimental", - "react-dom": "experimental", + "react": "canary", + "react-dom": "canary", "react-scripts": "^5.0.0" }, "main": "/index.js", @@ -223,8 +223,8 @@ function AddToCartForm({itemID, itemTitle}) { export default function App() { return ( <> - - + + ) } @@ -264,8 +264,8 @@ form button { ```json package.json hidden { "dependencies": { - "react": "experimental", - "react-dom": "experimental", + "react": "canary", + "react-dom": "canary", "react-scripts": "^5.0.0" }, "main": "/index.js", From 5cd8bb9175f06a032a41d5264a13c1c01b2db76d Mon Sep 17 00:00:00 2001 From: Xavi Lee Date: Thu, 26 Oct 2023 10:14:08 +0800 Subject: [PATCH 3/3] fix conflict --- src/content/reference/react-dom/hooks/index.md | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/src/content/reference/react-dom/hooks/index.md b/src/content/reference/react-dom/hooks/index.md index eeea3246b7..082edf86a0 100644 --- a/src/content/reference/react-dom/hooks/index.md +++ b/src/content/reference/react-dom/hooks/index.md @@ -20,13 +20,8 @@ Form Hooks 目前仅在 React canary 与 experimental 渠道中可用。在此 **Form** 允许创建用于提交信息的交互式控件。要在组件中管理表单，请使用以下其中一个 Hook： -<<<<<<< HEAD * [`useFormStatus`](/reference/react-dom/hooks/useFormStatus) 允许根据表单的状态更新用户界面。 -* `useFormState` 允许管理表单内部的状态。 -======= -* [`useFormStatus`](/reference/react-dom/hooks/useFormStatus) allows you to make updates to the UI based on the status of the a form. -* [`useFormState`](/reference/react-dom/hooks/useFormState) allows you to manage state inside a form. ->>>>>>> 6ef844b906a42cb9d70a5de15941dfce123e8f7d +* `useFormState`(/reference/react-dom/hooks/useFormState) 允许管理表单内部的状态。 ```js function Form({ action }) {