我目前正在使用JQuery，我有一个简单的问题。如何从下面的p标签获取信息？
HTML：
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<p> Hello there </p>
<p onclick="myFunction()"> Hello </p>
</body>
JS：
function myFunction() {
var result = $(this).prev('p');
alert(result)
}
但是我得到
[object Object]
希望有人可以帮助我。预先感谢
答案 0 :(得分：2)
从onclick属性调用函数时，this未设置为目标元素。您需要为函数指定一个参数，并显式传递this。
function myFunction(el) {
var result = $(el).prev('p');
alert(result.text());
}<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<p> Hello there </p>
<p onclick="myFunction(this)"> Hello </p>
答案 1 :(得分：1)
当前代码中的问题是，this中的myFunction()并未引用单击的元素，因为您为处理程序附加了on*事件属性。
要解决此问题并改善逻辑，请使用不显眼的事件处理程序。由于您已经在页面上添加了对jQuery的引用，因此可以使用click()，如下所示：
$(function() {
$('.foo').click(function() {
var result = $(this).prev('p').text();
console.log(result)
});
});<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<p>Hello there</p>
<p class="foo">Hello</p>
请注意，我在示例中显示了text()属性，因为它比显示带有其所有属性的整个对象要简洁得多。另外，请始终使用console.log()进行调试，而不要使用alert()进行调试，因为后者会强制使用会掩盖问题的数据类型。这也是令人讨厌的模态。
答案 2 :(得分：0)
您可以在=INDIRECT("'S\My\Question\Is[" & A1 & ".xlxs]Sheet2'!B1")
中传递<?php
if (!defined('_PS_VERSION_')) exit;
class BlockRealization extends Module {
protected $_html = '';
public function __construct() {
$this->name = 'blockrealization';
$this->tab = 'front_office_features';
$this->version = '1.0.0';
$this->author = 'XXX';
$this->need_instance = 0;
$this->ps_versions_compliancy = array('min' => '1.6', 'max' => _PS_VERSION_);
$this->bootstrap = true;
parent::__construct();
$this->displayName = $this->l('Module realization');
$this->description = $this->l('Display realization on homepage.');
$this->confirmUninstall = $this->l('Are you sure you want to uninstall?');
}
public function install() {
if (!parent::install() ||
!$this->registerHook('displayHeader') ||
!$this->registerHook('home') ||
!$this->createTables()
)
return false;
return true;
}
public function uninstall() {
if (!parent::uninstall() ||
!$this->removeTable())
return false;
return true;
}
protected function createTables() {
/* Realization */
$res = (bool)Db::getInstance()->execute('
CREATE TABLE IF NOT EXISTS `'._DB_PREFIX_.'realization` (
`id_realization_slides` int(10) unsigned NOT NULL AUTO_INCREMENT,
`image_realization` varchar(255) NOT NULL,
`position` int(10) unsigned NOT NULL,
PRIMARY KEY (`id_realization_slides`, `image_realization`)
) ENGINE='._MYSQL_ENGINE_.' DEFAULT CHARSET=UTF8;
');
return $res;
}
protected function removeTable() {
if (!Db::getInstance()->Execute('DROP TABLE `'. _DB_PREFIX_ . 'realization`'))
return false;
return true;
}
public function getContent() {
$output = null;
if (Tools::isSubmit('submit'.$this->name)) {
$errors = '';
if ($_FILES) {
$helper = new HelperImageUploader('realization_img');
$files = $helper->process();
if ($files) {
foreach ($files as $file) {
if (isset($file['save_path'])) {
if (!ImageManager::checkImageMemoryLimit($file['save_path']))
$errors = Tools::displayError('Limit');
if (!$errors) {
if (!ImageManager::resize($file['save_path'], dirname(__FILE__) . '/img/' . $file['name']))
$errors = Tools::displayError('error');
else {
$previous_file = Configuration::get('realization_img');
$file_path = dirname(__FILE__) . '/img/' . $previous_file;
if (file_exists($file_path))
unlink($file_path);
$realization['image_realization'] = $file['name'];
$realization['position'] = count($this->getAll());
if (!Db::getInstance()->insert('realization', $realization))
$errors = Tools::displayError('error');
}
}
unlink($file['save_path']);
}
}
}
}
if ($errors)
$output .= $this->displayError($errors);
else
$output .= $this->displayConfirmation($this->l('Settings updated'));
}
$output .= $this->generateList();
$output .= $this->displayForm();
return $output;
}
public function displayForm() {
// Init Fields form array
$fields_form[0]['form'] = array(
'legend' => array(
'title' => $this->l('Add the realization'),
),
'input' => array(
array(
'type' => 'file',
'label' => $this->l('Image:'),
'name' => 'realization_img',
'hint' => $this->l('Upload image for contact:'),
)
),
'submit' => array(
'title' => $this->l('Save'),
'class' => 'btn btn-default pull-right'
)
);
$helper = new HelperForm();
// Module, token and currentIndex
$helper->module = $this;
$helper->name_controller = $this->name;
$helper->token = Tools::getAdminTokenLite('AdminModules');
$helper->currentIndex = AdminController::$currentIndex.'&configure='.$this->name;
// Title and toolbar
$helper->title = $this->displayName;
$helper->show_toolbar = true; // false -> remove toolbar
$helper->toolbar_scroll = true; // yes - > Toolbar is always visible on the top of the screen.
$helper->submit_action = 'submit'.$this->name;
$helper->toolbar_btn = array(
'save' =>
array(
'desc' => $this->l('Save'),
'href' => AdminController::$currentIndex.'&configure='.$this->name.'&save'.$this->name.
'&token='.Tools::getAdminTokenLite('AdminModules'),
),
'back' => array(
'href' => AdminController::$currentIndex.'&token='.Tools::getAdminTokenLite('AdminModules'),
'desc' => $this->l('Back to list')
)
);
// Load current value
$helper->tpl_vars = array(
'fields_value' => array(
'realization_img' => Configuration::get('realization_img')
)
);
return $helper->generateForm($fields_form);
}
public function generateList() {
$content = $this->getAll();
$fields_list = array(
'id_realization_slides' => array(
'title' => 'ID',
'align' => 'center',
'class' => 'fixed-width-xs',
),
'image_realization' => array(
'title' => $this->l('Image'),
'orderby' => false,
'search' => false
),
'position' => array(
'title' => $this->l('Position'),
'position' => 'position' ,
'orderby' => false,
'search' => false
),
);
$helper = new HelperList();
$helper->shopLinkType = '';
$helper->actions = array('edit', 'delete');
$helper->module = $this;
$helper->listTotal = count($content);
$helper->identifier = 'id_realization_slides';
$helper->title = $this->l('Realizations');
$helper->table = $this->name;
$helper->imageType = 'jpg';
$helper->orderBy = 'position';
$helper->orderWay = 'asc';
$helper->position_identifier = 'id_realization_slides';
$helper->token = Tools::getAdminTokenLite('AdminModules');
$helper->currentIndex = AdminController::$currentIndex.'&configure='.$this->name;
return $helper->generateList($content, $fields_list);
}
public function getAll() {
return Db::getInstance()->ExecuteS('
SELECT *
FROM '._DB_PREFIX_.'realization
');
}
public function ajaxProcessUpdatePositions()
{
$way = (int)Tools::getValue('way');
$id_quicklinks = (int)Tools::getValue('id');
$positions = Tools::getValue('realization_slides');
if (is_array($positions))
foreach ($positions as $position => $value)
{
$pos = explode('_', $value);
if (isset($pos[2]) && (int)$pos[2] === $id_velcroquicklinks)
{
if (isset($position) && $this->updatePosition($way, $position, $id_quicklinks))
echo 'ok position '.(int)$position.' for id '.(int)$pos[1].'\r\n';
else
echo '{"hasError" : true, "errors" : "Can not update id '.(int)$id_quicklinks.' to position '.(int)$position.' "}';
break;
}
}
}
public function updatePosition($way, $position, $id)
{
if (!$res = Db::getInstance()->executeS('
SELECT `id_realization_slides`, `position`
FROM `'._DB_PREFIX_.'realization`
ORDER BY `position` ASC'
))
return false;
foreach ($res as $quicklinks)
if ((int)$quicklinks['id_realization_slides'] == (int)$id)
$moved_quicklinks = $quicklinks;
if (!isset($moved_quicklinks) || !isset($position))
return false;
return (Db::getInstance()->execute('
UPDATE `'._DB_PREFIX_.'realization`
SET `position`= `position` '.($way ? '- 1' : '+ 1').'
WHERE `position`
'.($way
? '> '.(int)$moved_quicklinks['position'].' AND `position` <= '.(int)$position
: '< '.(int)$moved_quicklinks['position'].' AND `position` >= '.(int)$position.'
'))
&& Db::getInstance()->execute('
UPDATE `'._DB_PREFIX_.'realization`
SET `position` = '.(int)$position.'
WHERE `id_realization_slides` = '.(int)$moved_quicklinks['id_quicklinks']));
}
public function hookHome($params) {
return $this->display(__FILE__, "views/templates/hook/realization.tpl");
}
并找到其this
onclickprev()答案 3 :(得分：0)
function myFunction(id) {
result = document.getElementById(id).innerHTML
alert(result)
}<p id ='myP' onclick="myFunction('myP')"> Hello </p>