What selectors does xml have?

xml has three most basic selectors: "element selector", "class selector" and "ID selector": 1. Element selector, the most basic selector, matches elements by element name ; 2. Class selector, matching elements by class name, the format is to add a dot "." before the class name; 3. ID selector, matching elements by ID, the format is adding a pound sign "#" before the ID .

# Operating system for this tutorial: Windows 10 system, Dell G3 computer.

There are the following selectors in XML:

1. Element selector: This is the most basic selector, matching elements by element name. For example, is an element selector that selects the element named "productame".
2. Class selector: Match elements by class name. The format of a class selector is to precede the class name with a dot (.). For example, .className is a class selector that selects elements with the class name "className".
3. ID selector: matches elements by ID. The format of the ID selector is to add a pound sign (#) before the ID. For example, #IDName is an ID selector that selects elements with the ID "IDName".

In addition to the above three basic selectors, there are other more complex selectors:

4. Descendant selectors: You can select the child elements of a specific element. For example, div p will select all p elements inside a div element.
5. Child element selector: You can select the direct child elements of a specific element. For example, div > p will select all p elements that are direct children of div elements.
6. Adjacent sibling selector: You can select the next or previous sibling element of a specific element. For example, h1 p will select all p elements immediately following the h1 element.
7. Attribute selector: You can select elements with specific attributes. For example, input[type="text"] will select all input elements of type "text".

Here is an example showing how to use these selectors:

<root>  
  <productame class="red">This is a product</productame>  
  <price class="blue">100</price>  
  <productame class="green">Another product</productame>  
</root>

In this example, these elements can be styled using the following CSS rules:

/* 使用元素选择器 */  
productame {  
  font-size: 20pt;  
}  
  
/* 使用类选择器 */  
.red {  
  color: red;  
}  
  
.blue {  
  color: blue;  
}  
  
/* 使用ID选择器 */  
#price {  
  color: green;  
}

In this CSS, the productame selector sets all elements to a font size of 20 points. The .red and .blue class selectors set elements with the corresponding class name to red or blue. The #price ID selector sets the element to green.

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