Server Functions are functions referenced on the client but executed on the server.
Here’s an example:
'use client'
import { useActionState } from "react";
import { updateName } from "@/app/react-19-server-function/actions";
export default function Page() {
const [error, submitAction, isPending] = useActionState(
async (_previousState, formData) => {
const error = await updateName(formData.get("name") as string);
if (error) {
return error;
}
return ""
},
"",
);
return <div>
<h1>React 19: Server Functions</h1>
<fieldset>
<div>Name</div>
<form action={submitAction}>
<input type="text" name="name" />
<button type="submit" disabled={isPending}>Save</button>
</form>
<div>
{error && <p>{error}</p>}
</div>
</fieldset>
</div>
}
Check my earlier post for more details on useActionState
Notice how updateName is imported.
import { updateName } from "@/app/react-19-server-function/actions";
and passed into useActionState.
This means that whenever the form is submitted, it runs submitAction, which then calls updateName.
Now, let’s check out updateName:
"use server";
export async function updateName(name) {
if (name?.length < 2) {
return "Name must be at least 2 characters.";
}
return "";
}
It’s a very simple function that checks the length of name. If it has less than 2 characters, it returns an error; otherwise, it returns an empty string, meaning no error.
Another thing to note is the directive: "use server". This tells React the function will be executed on the server, so it creates a reference the client can use.
The UI is super straightforward and looks like this:
If the form is submitted without any value, you’ll notice a POST network request with a few interesting details:
- content-type: is text/x-component.
- The payload is passed automatically, even though it’s empty.
- The response is kind of like JSON.
Links
- Codebase
Conclusion
Server Functions are functions that run on the server. The alternative is to manually use fetch to make a request to the backend and handle things like reading the status code and parsing the payload.
With Server Functions, you don’t need to worry about the communication part. Just create a function with the "use server" directive and import it into a client file, the framework takes care of the rest.
The above is the detailed content of React Server Functions. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Java vs. JavaScript: Clearing Up the Confusion
Jun 20, 2025 am 12:27 AM
Java and JavaScript are different programming languages, each suitable for different application scenarios. Java is used for large enterprise and mobile application development, while JavaScript is mainly used for web page development.
Javascript Comments: short explanation
Jun 19, 2025 am 12:40 AM
JavaScriptcommentsareessentialformaintaining,reading,andguidingcodeexecution.1)Single-linecommentsareusedforquickexplanations.2)Multi-linecommentsexplaincomplexlogicorprovidedetaileddocumentation.3)Inlinecommentsclarifyspecificpartsofcode.Bestpractic
How to work with dates and times in js?
Jul 01, 2025 am 01:27 AM
The following points should be noted when processing dates and time in JavaScript: 1. There are many ways to create Date objects. It is recommended to use ISO format strings to ensure compatibility; 2. Get and set time information can be obtained and set methods, and note that the month starts from 0; 3. Manually formatting dates requires strings, and third-party libraries can also be used; 4. It is recommended to use libraries that support time zones, such as Luxon. Mastering these key points can effectively avoid common mistakes.
JavaScript vs. Java: A Comprehensive Comparison for Developers
Jun 20, 2025 am 12:21 AM
JavaScriptispreferredforwebdevelopment,whileJavaisbetterforlarge-scalebackendsystemsandAndroidapps.1)JavaScriptexcelsincreatinginteractivewebexperienceswithitsdynamicnatureandDOMmanipulation.2)Javaoffersstrongtypingandobject-orientedfeatures,idealfor
Why should you place tags at the bottom of the ?
Jul 02, 2025 am 01:22 AM
PlacingtagsatthebottomofablogpostorwebpageservespracticalpurposesforSEO,userexperience,anddesign.1.IthelpswithSEObyallowingsearchenginestoaccesskeyword-relevanttagswithoutclutteringthemaincontent.2.Itimprovesuserexperiencebykeepingthefocusonthearticl
JavaScript: Exploring Data Types for Efficient Coding
Jun 20, 2025 am 12:46 AM
JavaScripthassevenfundamentaldatatypes:number,string,boolean,undefined,null,object,andsymbol.1)Numbersuseadouble-precisionformat,usefulforwidevaluerangesbutbecautiouswithfloating-pointarithmetic.2)Stringsareimmutable,useefficientconcatenationmethodsf
What is event bubbling and capturing in the DOM?
Jul 02, 2025 am 01:19 AM
Event capture and bubble are two stages of event propagation in DOM. Capture is from the top layer to the target element, and bubble is from the target element to the top layer. 1. Event capture is implemented by setting the useCapture parameter of addEventListener to true; 2. Event bubble is the default behavior, useCapture is set to false or omitted; 3. Event propagation can be used to prevent event propagation; 4. Event bubbling supports event delegation to improve dynamic content processing efficiency; 5. Capture can be used to intercept events in advance, such as logging or error processing. Understanding these two phases helps to accurately control the timing and how JavaScript responds to user operations.
What's the Difference Between Java and JavaScript?
Jun 17, 2025 am 09:17 AM
Java and JavaScript are different programming languages. 1.Java is a statically typed and compiled language, suitable for enterprise applications and large systems. 2. JavaScript is a dynamic type and interpreted language, mainly used for web interaction and front-end development.
