R rvest html_table 将 html 表解析为 DataFrame

html_table(
  x,
  header = NA,
  trim = TRUE,
  fill = deprecated(),
  dec = ".",
  na.strings = "NA",
  convert = TRUE
)

sample1 <- minimal_html("<table>
  <tr><th>Col A</th><th>Col B</th></tr>
  <tr><td>1</td><td>x</td></tr>
  <tr><td>4</td><td>y</td></tr>
  <tr><td>10</td><td>z</td></tr>
</table>")
sample1 %>%
  html_element("table") %>%
  html_table()
#> # A tibble: 3 × 2
#>   `Col A` `Col B`
#>     <int> <chr>  
#> 1       1 x      
#> 2       4 y      
#> 3      10 z      

# Values in merged cells will be duplicated
sample2 <- minimal_html("<table>
  <tr><th>A</th><th>B</th><th>C</th></tr>
  <tr><td>1</td><td>2</td><td>3</td></tr>
  <tr><td colspan='2'>4</td><td>5</td></tr>
  <tr><td>6</td><td colspan='2'>7</td></tr>
</table>")
sample2 %>%
  html_element("table") %>%
  html_table()
#> # A tibble: 3 × 3
#>       A     B     C
#>   <int> <int> <int>
#> 1     1     2     3
#> 2     4     4     5
#> 3     6     7     7

# If a row is missing cells, they'll be filled with NAs
sample3 <- minimal_html("<table>
  <tr><th>A</th><th>B</th><th>C</th></tr>
  <tr><td colspan='2'>1</td><td>2</td></tr>
  <tr><td colspan='2'>3</td></tr>
  <tr><td>4</td></tr>
</table>")
sample3 %>%
  html_element("table") %>%
  html_table()
#> # A tibble: 3 × 3
#>       A     B     C
#>   <int> <int> <int>
#> 1     1     1     2
#> 2     3     3    NA
#> 3     4    NA    NA