mirror of
https://github.com/msva/lua-htmlparser.git
synced 2024-11-27 12:44:22 +00:00
76 lines
2.7 KiB
Markdown
76 lines
2.7 KiB
Markdown
#LuaRock "htmlparser"
|
|
|
|
Parse HTML text into a tree of elements with selectors
|
|
|
|
###License
|
|
MIT; see ./doc/LICENSE
|
|
|
|
###Usage
|
|
Start off with
|
|
```lua
|
|
require("luarocks.loader")
|
|
local htmlparser = require("htmlparser")
|
|
```
|
|
Then, parse some html:
|
|
```lua
|
|
local root = htmlparser.parse(htmlstring)
|
|
```
|
|
The input to parse may be the contents of a complete html document, or any valid html snippet, as long as all tags are correctly opened and closed.
|
|
Now, find specific elements by selecting:
|
|
```lua
|
|
local elements = root:select(selectorstring)
|
|
```
|
|
Or in shorthand:
|
|
```lua
|
|
local elements = root(selectorstring)
|
|
```
|
|
This wil return a Set of elements, all of which are of the same type as the root element, and thus support selecting as well, if ever needed:
|
|
```lua
|
|
for e in pairs(elements) do
|
|
print(e.name)
|
|
local subs = e(subselectorstring)
|
|
for sub in pairs(subs) do
|
|
print("", sub.name)
|
|
end
|
|
end
|
|
```
|
|
|
|
###Selectors
|
|
- "element"
|
|
- "#id"
|
|
- ".class"
|
|
- "[attribute]"
|
|
- "[attribute=value]"
|
|
- "[attribute!=value]"
|
|
- "[attribute|=value]"
|
|
- "[attribute*=value]"
|
|
- "[attribute~=value]"
|
|
- "[attribute^=value]"
|
|
- "[attribute$=value]"
|
|
- ":not(selector)"
|
|
- "ancestor descendant"
|
|
- "parent > child"
|
|
Selectors can be combined; e.g. ".class:not([attribute]) element.class"
|
|
|
|
####Limitations
|
|
- Attribute values in selectors currently cannot contain any spaces, since space is interpreted as a delimiter between ancestor and descendant, parent and >, or > and child parts of the selector
|
|
- Likewise, for the parent > child relation, the spaces before and after the > are mandatory
|
|
|
|
###Element type
|
|
The tree elements provide, apart from :select and (), the following accessors:
|
|
- .name = the elements tagname
|
|
- .attributes = a table with keys and values for the element's attributes
|
|
- .id = the value of the element's id attribute, if present
|
|
- .classes = an array with the classes listed in element's class attribute, if any
|
|
- :getcontent() = the raw text between the opening and closing tags of the element
|
|
- .nodes = an array with the element's child elements
|
|
- .parent = the elements that contains this element; root.parent is nil
|
|
- :gettext() = the raw text of the complete element, starting with `"<tagname"` and ending with `"/>"`
|
|
- .level = how deep the element is in the tree; root level is 0
|
|
- .root the root element of the tree; root.root is root
|
|
- .deepernodes = a Set containing all elements in the tree beneath this element, including this element's .nodes
|
|
- .deeperelements = a table with a key for each distinct tagname in .deepernodes, containing a Set of all deeper element nodes with that name
|
|
- .deeperattributes = as .deeperelements, but keyed on attribute name
|
|
- .deeperids = as .deeperelements, but keyed on id value
|
|
- .deeperclasses = as .deeperelements, but keyed on class name
|