用hxt提取多个html表格 [英] extract multiples html tables with hxt

问题描述

我的问题是我必须从html文档中提取所有表格，并将它们放在表格列表中。

因此，我明白结束函数类型应该是

  getTable :: a [XmlTree] [[String]] 
  

例如使用以下xml：

 < table class =t1> 
< tr> 
< td> x< / td> 
< td> y< / td> 
< / tr> 
< tr> 
< td> a< / td> 
< td> b< / td> 
< / tr> 
< / table> 
< table class =t2> 
< tr> 
< td> 3< / td> 
< td> 5< / td> 
< / tr> 
< tr> 
< td> toto< / td> 
< td> titi< / td> 
< / tr> 
< / table> 
  

我知道如何从一个xmlTree（example1）或所有标签tables它为我提供了[XmlTree]类型，但我不知道如何在test2的结果中映射箭头example1。

我确定它很明显，但我找不到它。

  test2 :: IO [[XmlTree]] 
 test2 = runX $ parseXMLtable.xml>> ;>是表格>>> listA getChildren 
 
 example1 :: ArrowXml a => XmlTree [String] 
 example1 = istable/> listA（getChildren>>>是td/> getText）
  

解决方案

使用与 example1 相同的一般思想，我们可以这样写 getTable

  getTable :: ArrowXml a => XmlTree [[String]] 
 getTable = hasNametable>>> listA（rows>>> listA cols）其中
 rows = getChildren>>> hasNametr
 cols = getChildren>>> hasNametd/> getText 
  

运行示例文档中的箭头产生

  [[[ X， Y]，[ 一， b]]，[[ 3， 5]，[ TOTO ，titi]]] 
  

my problem is i have to extracts all of tables from an html document and put them in a list of tables.

Hence i understand that the ending function type should be

getTable :: a [XmlTree] [[String]]

for example with the following xml:

<table class="t1">
<tr>
    <td>x</td>
    <td>y</td>
</tr>
<tr>
    <td>a</td>
    <td>b</td>
</tr>
</table>
<table class="t2">
<tr>
    <td>3</td>
    <td>5</td>
</tr>
<tr>
    <td>toto</td>
    <td>titi</td>
</tr>
</table>

i know how to retrieve all the rows from one xmlTree (example1) or all the tags "tables" which provides me the type [XmlTree], but i don't know how to map the arrow example1 inside the result of test2.

I'm sure its obvious but i can't find it.

test2 ::  IO [[XmlTree]]
test2 = runX $ parseXML "table.xml" >>> is "table">>> listA getChildren

example1 ::  ArrowXml a => a XmlTree [String]
example1  = is "table" /> listA (getChildren >>> is "td"  /> getText)

解决方案

Using the same general idea that you have in example1, we can write getTable like this

getTable :: ArrowXml a => a XmlTree [[String]]
getTable =  hasName "table" >>> listA (rows >>> listA cols) where
    rows = getChildren >>> hasName "tr"
    cols = getChildren >>> hasName "td" /> getText

Running the arrow on your example document produces

[[["x","y"],["a","b"]],[["3","5"],["toto","titi"]]]

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