Web page design of jQuery_4. jQuery manipulates DOM elements (on)

1. Use jQuery to get the content or attributes of DOM elements

A very important part of jQuery is the ability to manipulate the DOM.

jQuery provides a series of DOM-related methods, which makes it easy to access and manipulate elements and attributes.

Before that, let me talk about what DOM is

JUDGMENT

The full name of DOM is Document Object Model. To put it bluntly, it is our tag, like the <p> tag, this is a DOM node

Then let's take a look at how to get the content or attributes of DOM elements

1. Get content

There are three ways to get content

  • text()-Set or return the text content of the selected element
  • html()-Set or return the content of the selected element (including HTML markup)
  • val()-Set or return the value of a form field

Let's take a look at how to use

text()

We click the button

As you can see, we have obtained all the content in the p tag, including the strong tag

html()

It’s the same example just now, we only need to modify the text to html, let’s take a look at the effect

As you can see, we not only get the content, but also the tags

val()

val is actually used to get the value of the DOM node, let’s look at it again

Let's run it

As you can see, there is no problem

2. Get properties

Let's take a look at how to get attributes. To get the attribute, we need to use the attr method, and then we need to pass in a parameter, for example, if we want to get an id, then we pass an id, if we get a value, then we pass a value, let’s take a look

Run it

Let's get another type

Also ok

2. Use jQuery to set the content or attributes of DOM elements

In fact, this setting value is very similar to the obtained value, I hope you can draw inferences about it.

1. Set the value of the DOM element content

text()

We click the button

html()

The difference between html and text, html can set some tag values, let’s take a look

Then we click the button

Is OK, just replace it with button

val()

This is the same, it is to set the value of the tag with the value attribute such as input, let's take a look

Click button

OK

2. Set attributes to DOM element content

Properties are also very easy, let’s take a look

Let's click on the button to see if we can use the style of a

Ok, no problem

Three, use jQuery to modify the css style

We can modify the style of css through jQuery, let's take a look at an example

Then we click on the button to see the effect

OK, but if we want to make this yellow background, but also enlarge the text, how do we do this? Of course, jQuery has already thought about it for us, let’s take a look

We only need to define it as a json string, let’s click and try

There is no problem

 

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Origin blog.csdn.net/weixin_45908370/article/details/109698094