HTML Selector

DOCS

An HTML content extraction tool similar to CSS selectors that can precisely extract and process the required content from HTML documents through a simple and intuitive query language.

Example

use query::Query;

fn main() {
    let html = r#"
    <div class="a">
        <p>text 1</p>
        <p>text 2</p>
        <p>text 3</p>
    </div>
    <div class="b">
        <p>text 4</p>
        <p>text 5</p>
        <p>text 6</p>
    </div>
    "#;
    let q = Query::new(html);
    let result = q.query(r#"(class a > tag p:1:2 | class b > tag p:0) > text @replace," ","""#).texts();
    println!("{:?}", result); // ["text2", "text3", "text4"]
}

Basic Selectors

Text Extraction

Pipeline Operations

The pipeline operator > is used to connect multiple selectors for layer-by-layer querying:

class main > tag p > text

This query first selects elements with the class "main", then finds p tags within them, and finally extracts the text content of these p tags.

Regular Expression Matching

Using the tilde ~ allows for regular expression matching:

class ~".*ain" > tag p > text

This query selects elements with class names matching the regular expression .*ain, for example, it can match "main", "again", etc.

Index Selection

You can add an index after the selector to select elements at specific positions:

Text Processing Functions

Using the @ symbol can invoke built-in text processing functions:

Function Parameter Types

Multiple functions can be chained:

class main > text @trim @replace,A,a @lowercase

Set Operations

Complex set operations can be grouped with parentheses:

(((class a ^ class c) | class b) > tag a | class main > tag a) > text @trim

Update History

0.1.8 (2025.04.29)

1. Optimized the lexical analysis of float literal.

2. Added nil.

3. Added a new slice function for string slicing.

   @slice,1,5. When the parameter is nil, @slice,nil,5 is equivalent to @slice,0,5, and @slice,0,nil is equivalent to @slice,0,(str.len()).

0.1.7 (2025.04.28)

1. Improved the index selection feature, which now allows for:

   tag p:-1,-2

   tag p:10:2:-2

   tag p:::-1

   tag p:-1:-4

0.1.5 (2025.04.28)

1. Added the # operator for selecting attribute text values.

   class main > tag a > #target (or #~".*rget")

2. Added parsing of function parameters for int, float, bool, str and list types.

   Note: For the str type not wrapped in ", there must be at least one space between the last value in the list and ], for example: [test1, test2 ].

3. Add a new function in.

   @in,["text1", text2 ]