search
HomeWeb Front-endHTML TutorialDetailed explanation of the subtle differences between Readonly and Disabled

Both Readonly and Disabled can prevent users from changing the content in the form field, but there are still certain differences between them. The following is a detailed introduction to you. Both Readonly and Disabled can prevent users from changing the contents of form fields. But there are slight differences between them, which are summarized as follows:

Readonly is only valid for input (text / password) and textarea, while disabled is valid for all form elements, but after the form element uses disabled, When we submit the form via POST or GET, the value of this element will not be passed out, but readonly will pass the value out (readonly accepts value changes and can return them, disable accepts changes but does not return data).

Generally common situations are:

A unique identification code is pre-filled in a form for the user, and the user is not allowed to change it, but the value needs to be passed when submitting. Its property should be set to readonly.

It is often encountered that when a user formally submits a form and needs to wait for information verification by the administrator, the user is not allowed to change the data in the form, but can only view it. Due to the large range of disabled elements, Therefore, disabled should be used at this time, but at the same time, it should be noted that the submit button should also be disabled. Otherwise, as long as the user presses this button, if there is no integrity check in the database operation page, the values ​​in the database will be cleared. . If readonly is used instead of disabled in this case, it is still possible if there are only input (text/password) and textarea elements in the form. If there are other elements, such as select, the user can rewrite the value and press Press the Enter key to submit (Enter is the default submit trigger key)

We often use javascript to disable the submit button after the user presses the submit button. This can prevent the user from using the submit button in an environment with poor network conditions. The user repeatedly clicks the submit button causing data to be redundantly stored in the database.

The two attributes disabled and readonly have something in common. For example, if both are set to true, the form attribute cannot be edited. It is often easy to mix these two attributes when writing js code. In fact, they There are certain differences between them:

If the disabled of an input item is set to true, the form input item cannot obtain focus, and all user operations (mouse clicks and keyboard input, etc.) will affect the input item. Invalid, the most important point is that when the form is submitted, this form input will not be submitted.
Readonly is only for input items such as text input boxes that can input text. If set to true, the user just cannot edit the corresponding text, but can still focus, and when submitting the form, the input item will be used as A submission of the form.

For more detailed explanations of the subtle differences between Readonly and Disabled, please pay attention to the PHP Chinese website for related articles!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
HTML: Is It a Programming Language or Something Else?HTML: Is It a Programming Language or Something Else?Apr 15, 2025 am 12:13 AM

HTMLisnotaprogramminglanguage;itisamarkuplanguage.1)HTMLstructuresandformatswebcontentusingtags.2)ItworkswithCSSforstylingandJavaScriptforinteractivity,enhancingwebdevelopment.

HTML: Building the Structure of Web PagesHTML: Building the Structure of Web PagesApr 14, 2025 am 12:14 AM

HTML is the cornerstone of building web page structure. 1. HTML defines the content structure and semantics, and uses, etc. tags. 2. Provide semantic markers, such as, etc., to improve SEO effect. 3. To realize user interaction through tags, pay attention to form verification. 4. Use advanced elements such as, combined with JavaScript to achieve dynamic effects. 5. Common errors include unclosed labels and unquoted attribute values, and verification tools are required. 6. Optimization strategies include reducing HTTP requests, compressing HTML, using semantic tags, etc.

From Text to Websites: The Power of HTMLFrom Text to Websites: The Power of HTMLApr 13, 2025 am 12:07 AM

HTML is a language used to build web pages, defining web page structure and content through tags and attributes. 1) HTML organizes document structure through tags, such as,. 2) The browser parses HTML to build the DOM and renders the web page. 3) New features of HTML5, such as, enhance multimedia functions. 4) Common errors include unclosed labels and unquoted attribute values. 5) Optimization suggestions include using semantic tags and reducing file size.

Understanding HTML, CSS, and JavaScript: A Beginner's GuideUnderstanding HTML, CSS, and JavaScript: A Beginner's GuideApr 12, 2025 am 12:02 AM

WebdevelopmentreliesonHTML,CSS,andJavaScript:1)HTMLstructurescontent,2)CSSstylesit,and3)JavaScriptaddsinteractivity,formingthebasisofmodernwebexperiences.

The Role of HTML: Structuring Web ContentThe Role of HTML: Structuring Web ContentApr 11, 2025 am 12:12 AM

The role of HTML is to define the structure and content of a web page through tags and attributes. 1. HTML organizes content through tags such as , making it easy to read and understand. 2. Use semantic tags such as, etc. to enhance accessibility and SEO. 3. Optimizing HTML code can improve web page loading speed and user experience.

HTML and Code: A Closer Look at the TerminologyHTML and Code: A Closer Look at the TerminologyApr 10, 2025 am 09:28 AM

HTMLisaspecifictypeofcodefocusedonstructuringwebcontent,while"code"broadlyincludeslanguageslikeJavaScriptandPythonforfunctionality.1)HTMLdefineswebpagestructureusingtags.2)"Code"encompassesawiderrangeoflanguagesforlogicandinteract

HTML, CSS, and JavaScript: Essential Tools for Web DevelopersHTML, CSS, and JavaScript: Essential Tools for Web DevelopersApr 09, 2025 am 12:12 AM

HTML, CSS and JavaScript are the three pillars of web development. 1. HTML defines the web page structure and uses tags such as, etc. 2. CSS controls the web page style, using selectors and attributes such as color, font-size, etc. 3. JavaScript realizes dynamic effects and interaction, through event monitoring and DOM operations.

The Roles of HTML, CSS, and JavaScript: Core ResponsibilitiesThe Roles of HTML, CSS, and JavaScript: Core ResponsibilitiesApr 08, 2025 pm 07:05 PM

HTML defines the web structure, CSS is responsible for style and layout, and JavaScript gives dynamic interaction. The three perform their duties in web development and jointly build a colorful website.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
WWE 2K25: How To Unlock Everything In MyRise
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

DVWA

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

SAP NetWeaver Server Adapter for Eclipse

SAP NetWeaver Server Adapter for Eclipse

Integrate Eclipse with SAP NetWeaver application server.