在我的项目中，我有一个封装到两个div中的选择，我必须从javascript的选择中获取文本或值。
<RNCamera
ref={ref => {
this.camera = ref;
}}
style={styles.preview}
type={RNCamera.Constants.Type.back}
flashMode={RNCamera.Constants.FlashMode.on}
androidCameraPermissionOptions={{
title: 'Permission to use camera',
message: 'We need your permission to use your camera',
buttonPositive: 'Ok',
buttonNegative: 'Cancel',
}}
androidRecordAudioPermissionOptions={{
title: 'Permission to use audio recording',
message: 'We need your permission to use your audio',
buttonPositive: 'Ok',
buttonNegative: 'Cancel',
}}
onGoogleVisionBarcodesDetected={({ barcodes }) => {
console.log(barcodes);
}}
/>
我尝试以下代码：
<div class="col-lg-3 col-xs-6" id="div1">
<div class="form-group" id="divTtype">
<label>Templte Type:</label>
<select class="form-control" id="ftype">
<option value="..All">..All</option>
<option value="Functional">Functional</option>
<option value="Non Functional">Non Functional</option>
</select>
</div>
</div>
但是当我尝试时：
function GetElementInsideContainer(containerID, childID) {
var elm = document.getElementById(childID);
var parent = elm ? elm.parentNode : {};
return (parent.id && parent.id === containerID) ? elm : {};
}
一个“未定义”的回复给我。
我如何获得我选择的值？
非常感谢
答案 0 :(得分：2)
实际上，您的HTML代码“ divTtype”中有一个错字，您打算编写divType
<div class="col-lg-3 col-xs-6" id="div1">
<div class="form-group" id="divType">
<label>Templte Type:</label>
<select class="form-control" id="ftype">
<option value="..All">..All</option>
<option value="Functional">Functional</option>
<option value="Non Functional">Non Functional</option>
</select>
</div>
</div>
此外，您需要使用textContent属性而不是text
最后请使用"id"调用该函数，否则您将调用未定义的变量divType和ftype
console.log(GetElementInsideContainer("divType", "ftype"));
这当然可以解决您当前的问题，尽管请参考拉斐尔的答案以寻求更好的方法。
答案 1 :(得分：1)
答案 2 :(得分：1)
在将字符串作为参数发送时，应使用引号：
GetElementInsideContainer('divType', 'ftype').text;
答案 3 :(得分：1)
就像克里希纳（Krishna）在上述评论中所说，您应该能够这样做：
var select = document.getElementById('ftype')
var val = select.options[select.selectedIndex].value
您不必引用父节点。
答案 4 :(得分：1)
使用 textContent 并以 string 的形式传递ID，否则将其作为变量
其次，您具有id divTtype ，并且正在传递 divType
import time
from bs4 import BeautifulSoup as soup
import requests
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
import json
# The path to where you have your chrome webdriver stored:
webdriver_path = '/Users/rawlins/Downloads/chromedriver'
# Add arguments telling Selenium to not actually open a window
chrome_options = Options()
chrome_options.add_argument('--headless')
#chrome_options.add_argument('--window-size=1920x1080')
# Fire up the headless browser
browser = webdriver.Chrome(executable_path = webdriver_path,
chrome_options = chrome_options)
# Load webpage
url = "https://cnx.org/search?q=subject:Arts"
browser.get(url)
# to ensure that the page has loaded completely.
time.sleep(3)
data = []
n = 2
for i in range(1, n+1):
if (i == 1):
# handle first page
response = requests.get(url)
response = requests.get(url + "&page=" + str(i))
#response = requests.get(url + "&page=" + str(i),headers={'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.47 Safari/537.36'})
# Parse HTML, close browser
page_soup = soup(browser.page_source, 'lxml')
containers = page_soup.findAll("tr")
browser.quit()
for container in containers:
item = {}
item['type'] = "Course Material"
if container.find('td', {'class' : 'title'}):
item['title'] = container.find('td', {'class' : 'title'}).h4.text.strip()
else:
item['title'] = ""
if container.find('td', {'class' : 'authors'}):
item['author'] = container.find('td', {'class' : 'authors'}).text.strip()
else:
item['author'] = ""
if container.find('td', {'class' : 'title'}):
item['link'] = "https://cnx.org/" + container.find('td', {'class' : 'title'}).a["href"]
else:
item['link'] = ""
if container.find('td', {'class' : 'title'}):
item['description'] = container.find('td', {'class' : 'title'}).span.text
else:
item['description'] = ""
item['subject'] = "Arts"
item['source'] = "OpenStax CNX"
item['base_url'] = "https://cnx.org/browse"
item['license'] = "Attribution"
data.append(item) # add the item to the list
with open("js-webscrape.json", "w") as writeJSON:
json.dump(data, writeJSON, ensure_ascii=False)
function GetElementInsideContainer(containerID, childID) {
var elm = document.getElementById(childID);
var parent = elm ? elm.parentNode : {};
return (parent.id && parent.id === containerID) ? elm : {};
}
var a = GetElementInsideContainer("divType", "ftype").textContent;
console.log(a)
答案 5 :(得分：1)
似乎在这里工作正常。
<div class="col-lg-3 col-xs-6" id="div1">
<div class="form-group" id="divTtype">
<label>Templte Type:</label>
<select class="form-control" id="ftype">
<option value="..All">..All</option>
<option value="Functional">Functional</option>
<option value="Non Functional">Non Functional</option>
</select>
</div>
</div>
<button onclick="getSelected(GetElementInsideContainer('divTtype', 'ftype'))">Get Selected Value</button>
<script>
function getSelected(objEl)
{
alert(objEl.options[objEl.selectedIndex].text);
}
function GetElementInsideContainer(containerID, childID) {
var elm = document.getElementById(childID);
var parent = elm ? elm.parentNode : {};
return (parent.id && parent.id === containerID) ? elm : {};
}
</script>
答案 6 :(得分：1)
您需要选择的选择值吗？
我做了那段代码并获得了所选内容的HTML。 使用此代码段，您可以获得select的值
<div class="col-lg-3 col-xs-6" id="div1">
<div class="form-group" id="divTtype">
<label>Templte Type:</label>
<select class="form-control" id="ftype">
<option value="..All">..All</option>
<option value="Functional">Functional</option>
<option value="Non Functional">Non Functional</option>
</select>
</div>
</div>
function GetElementInsideContainer( childID) {
var elm = document.getElementById(childID);
console.log(elm.value)
return elm.value;
}
GetElementInsideContainer('ftype');
我认为您可能在参数中输入了错误的ID