我有這段 HTML
<div id="ctl00_cphMain_upAseguradora">
<ul>
<li>
Régimen de Afiliación(*)
<select name="ctl00$cphMain$ddlRegimenAfiliacion" id="ctl00_cphMain_ddlRegimenAfiliacion" disabled="disabled" class="aspNetDisabled comboBox">
<option value="0">-Seleccione-</option>
<option selected="selected" value="58">Contributivo</option>
<option value="61">Especial</option>
<option value="60">Pobre no afiliado</option>
<option value="59">Subsidiado</option>
</select>
</li>
</ul>
</div>對于網站的這一部分
與selectorgadget我找到該元素，我需要，但如何提取所選擇的選項IM不確定，在這種情況下，將是“Contributivo”
Regimen = detallepersona %>% html_elements("#ctl00_cphMain_upAseguradora ul:nth-child(1) li:nth-child(1) option")
paste(Regimen)
[1] "<option value=\"0\">-Seleccione-</option>\n" "<option selected value=\"58\">Contributivo</option>\n"
[3] "<option value=\"61\">Especial</option>\n" "<option value=\"60\">Pobre no afiliado</option>\n"
[5] "<option value=\"59\">Subsidiado</option>"
Regimen %>% html_attr("selected")
[1] NA "selected" NA NA NA
Regimen %>% html_text()
[1] "-Seleccione-" "Contributivo" "Especial" "Pobre no afiliado" "Subsidiado"
uj5u.com熱心網友回復：
Regimen = detallepersona %>% html_elements("#ctl00_cphMain_upAseguradora ul:nth-child(1) li:nth-child(1) option")
Regimen1 = Regimen %>% html_attr("selected")
Regimen1 = !is.na(Regimen1)
Regimen = Regimen %>% html_text()
Regimen[Regimen1]
[1] "Contributivo"
uj5u.com熱心網友回復：
使用 attribute 或 attribute = value css 選擇器將select具有 id的父元素的子元素定位ctl00_cphMain_ddlRegimenAfiliacion為該selected屬性。下面的 css 選擇器中的空格是一個后代組合器。
#ctl00_cphMain_ddlRegimenAfiliacion [selected]
或者
#ctl00_cphMain_ddlRegimenAfiliacion [selected=selected]
例如
Regimen = detallepersona %>% html_element('#ctl00_cphMain_ddlRegimenAfiliacion [selected]')%>%html_text()
閱讀更多：
- https://developer.mozilla.org/en-US/docs/Web/CSS/Attribute_selectors
- https://developer.mozilla.org/en-US/docs/Web/CSS/Descendant_combinator
轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/340872.html