


How to dynamically change the readOnly property of input without relying on JavaScript using PHP?
Apr 01, 2025 pm 02:36 PMGet rid of JavaScript and dynamically adjust the readOnly property of input with PHP
In web form development, it is very common to dynamically control readOnly
property of the input box. Many developers believe that this can only be achieved through JavaScript, but it is not. This article will demonstrate how to achieve this using PHP only without any JavaScript code.
Some users tried to dynamically modify the readOnly
attribute using the following PHP code, but the results were not good:
<input type="text" value="<?php echo isset($_GET['username']) ? $_GET['username'] : ''; ?>">
The problem is that readOnly
property is not a simple boolean switch. As long as readOnly
property exists, regardless of its value is true
or false
, the input box will be read-only.
The correct PHP code should dynamically add or remove readOnly
property itself:
<input type="text" value="<?php echo isset($_GET['username']) ? $_GET['username'] : ''; ?>" if echo>>
Decide whether to output readonly
attribute by adding conditional judgment ( /*此處添加你的條件判斷*/
). If the condition is true, add the readonly
property to make the input box read-only; otherwise, the property is not added and the input box remains editable. This cleverly uses PHP to achieve the purpose of dynamically controlling readOnly
attribute.
This method completely avoids the participation of JavaScript, making it more concise and efficient.
The above is the detailed content of How to dynamically change the readOnly property of input without relying on JavaScript using PHP?. For more information, please follow other related articles on the PHP Chinese website!

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