There are several ways to disable form controls in HTML

This time I will bring you disabling forms in HTMLControlsThere are several ways to disable form controls in HTMLNotesWhat are the practical cases below? Let’s take a look. one time.

In the process of making web pages, we often use forms. But sometimes we want the controls on the form to be unmodifiable. For example, in a web page for changing passwords, the text box that displays the user name should be unmodifiablestatus.
There are two disabling methods in html, they are:

1.给控件标签加上readonly='readonly'属性 
2.给控件标签加上disabled='disabled'属性

Example:

<input type="text" value="只读的" readonly="readonly" /> 
<input type="text" value="不可用的" disabled="disabled" />

The two controls in the example cannot be modified. . But they also have some differences!
From the literal meaning, we can know that the control using the readonly attribute is "read-only", while the control using disabled is "disabled". So what's the difference between them?
Read-only controls (controls that use the readonly attribute) cannot be modified by users with the mouse and keyboard, but programmers can modify them with javascript. When submitting the form, this control The name and value will be submitted to the server, which means they are visible to the server.
The disabled control (control using the disabled attribute) not only cannot be modified by the user with the mouse and keyboard, but also is invisible to the server, that is, its name and value will not be submitted to the server when the form is submitted. Of course, Programmers can also use JavaScript to modify its value.
This is their difference. After knowing the difference, we should know when to use which method. We must not be blind!

I believe you have mastered the methods after reading these cases. For more exciting information, please pay attention to other related articles on the php Chinese website!

Related reading:

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htmlHow to add attributes using style example

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