在 Javascript 中突出显示单词 - 为什么在页面完全加载后它们不会保持突出显示?



这是继@Drakes之前在这个问题上所做的出色工作之后的一个问题:用Javascript突出显示单词,我缺少什么?。

解决方案是通过找到"#cat"或"#dog"并将其替换为来突出显示单词

<span class='cat'>#CAT</span>

<span class='dog'>#DOG</span>

然后我们可以用CSS控制span标签的背景颜色。

这种效果很好,但背景色只保留了很短的一段时间就消失了。仔细一看,跨度标签似乎应用正确,然后突然再次删除。

下面是一个实际的工作示例,供您查看,并添加登录详细信息以运行任何测试和查看聊天
[已删除,不再存在]

以下是上一个问题中的更新代码,该问题当前正在工作示例中运行。

再次感谢任何进一步的帮助。如果您需要任何其他信息,请告诉我!

Javascript:

// NOTE: I needed to define these variables to make the demo work
var ajaxurl = "http://ip.jsontest.com/";
var chatroom_slug = "1";
var last_update_id = "1";
var last_update_received = 0;
function chatroom_check_updates() {
jQuery.post(
ajaxurl,
{
action: 'check_updates',
chatroom_slug: chatroom_slug,
last_update_id: last_update_id
},
function (response) {

// NOTE: the response is bad, an exception will be thrown, not NULL
chats = null;
try {
chats = jQuery.parseJSON( response );
} catch(e) {}
// NOTE: In this test, I don't know your URL, so I just commented out the bit below
if (1 || chats !== null ) {
for ( i = 0; i < chats.length; i++ ) {
if ( jQuery('div.chat-container div.chat-message-'+chats[i].id).length )
continue;
jQuery('div.chat-container').html( jQuery('div.chat-container').html() + chatroom_strip_slashes(chats[i].html) );
last_update_id = chats[i].id;
jQuery('div.chat-container').animate({ scrollTop: jQuery('div.chat-container')[0].scrollHeight - jQuery('div.chat-container').height() }, 100);
}
jQuery('.chat').each(function(){
var hashtag = jQuery(this).text()
.replace(/#dog/g, "<span class='dog'>#DOG</span>")
.replace(/#cat/g, "<span class='cat'>#CAT</span>");
jQuery(this).html(hashtag);
});
}
}
)
.error(function(xhr, status, error){
alert(xhr.responseText);
});
// I commented this out just for testing.
setTimeout( chatroom_check_updates, 1000 );
}
function chatroom_strip_slashes(str) {
return (str + '').replace(/\(.?)/g, function (s, n1) {
switch (n1) {
case '\':
return '\';
case '0':
return 'u0000';
case '':
return '';
default:
return n1;
}
});
}
jQuery(document).ready( function() {
last_update_id = 0;
chatroom_check_updates();
jQuery( 'textarea.chat-text-entry' ).keypress( function( event ) {
if ( event.charCode == 13 || event.keyCode == 13 ) {
chatroom_send_message();
return false;
}
});
});
function chatroom_send_message() {
message = jQuery( 'textarea.chat-text-entry' ).val();
jQuery( 'textarea.chat-text-entry' ).val('');
jQuery.post(
ajaxurl,
{
action: 'send_message',
chatroom_slug: chatroom_slug,
message: message
},
function (response) {
}
);
}

PHP:

<?php
/*
Plugin Name: Chat Room
Plugin URI: http://webdevstudios.com/support/wordpress-plugins/
Description: Chat Room for WordPress
Author: WebDevStudios.com
Version: 0.1.2
Author URI: http://webdevstudios.com/
License: GPLv2 or later
*/
Class Chatroom {
function __construct() {
register_activation_hook( __FILE__, array( $this, 'activation_hook' ) );
register_deactivation_hook( __FILE__, array( $this, 'deactivation_hook' ) );
add_action( 'init', array( $this, 'register_post_types' ) );
add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_scripts' ) );
add_action( 'save_post', array( $this, 'maybe_create_chatroom_log_file' ), 10, 2 );
add_action( 'wp_head', array( $this, 'define_javascript_variables' ) );
add_action( 'wp_ajax_check_updates', array( $this, 'ajax_check_updates_handler' ) );
add_action( 'wp_ajax_send_message', array( $this, 'ajax_send_message_handler' ) );
add_filter( 'the_content', array( $this, 'the_content_filter' ) );
}
function activation_hook() {
$this->register_post_types();
flush_rewrite_rules();
}
function deactivation_hook() {
flush_rewrite_rules();
}
function register_post_types() {
$labels = array(
'name' => _x( 'Chat Rooms', 'post type general name', 'chatroom' ),
'singular_name' => _x( 'Chat Room', 'post type singular name', 'chatroom' ),
'add_new' => _x( 'Add New', 'book', 'chatroom' ),
'add_new_item' => __( 'Add New Chat Room', 'chatroom' ),
'edit_item' => __( 'Edit Chat Room', 'chatroom' ),
'new_item' => __( 'New Chat Room', 'chatroom' ),
'all_items' => __( 'All Chat Rooms', 'chatroom' ),
'view_item' => __( 'View Chat Room', 'chatroom' ),
'search_items' => __( 'Search Chat Rooms', 'chatroom' ),
'not_found' => __( 'No Chat Rooms found', 'chatroom' ),
'not_found_in_trash' => __( 'No Chat Rooms found in Trash', 'chatroom' ),
'parent_item_colon' => '',
'menu_name' => __( 'Chat Rooms', 'chatroom' )
);
$args = array(
'labels' => $labels,
'public' => true,
'publicly_queryable' => true,
'show_ui' => true,
'show_in_menu' => true,
'query_var' => true,
'capability_type' => 'post',
'has_archive' => true,
'hierarchical' => false,
'menu_position' => null,
'show_in_nav_menus' => true,
'supports' => array( 'title' )
);
register_post_type( 'chat-room', $args );
}
function enqueue_scripts() {
global $post;
if ( $post->post_type != 'chat-room' )
return;
wp_enqueue_script( 'jquery' );
wp_enqueue_script( 'chat-room', plugins_url( 'chat-room.js', __FILE__ ) );
wp_enqueue_style( 'chat-room-styles', plugins_url( 'chat-room.css', __FILE__ ) );
}
function maybe_create_chatroom_log_file( $post_id, $post ) {
if ( empty( $post->post_type ) || $post->post_type != 'chat-room' )
return;
$upload_dir = wp_upload_dir();
$log_filename = $upload_dir['basedir'] . '/chatter/' . $post->post_name . '-' . date( 'm-d-y', time() );
if ( file_exists( $log_filename ) )
return;
wp_mkdir_p( $upload_dir['basedir'] . '/chatter/' );
$handle = fopen( $log_filename, 'w' );
fwrite( $handle, json_encode( array() ) );
// TODO create warnings if the user can't create a file, and suggest putting FTP creds in wp-config
}
function define_javascript_variables() {
global $post;
if ( empty( $post->post_type ) || $post->post_type != 'chat-room' )
return; ?>
<script>
var ajaxurl = '<?php echo admin_url( 'admin-ajax.php' ); ?>';
var chatroom_slug = '<?echo $post->post_name; ?>';
</script>
<?php
}
function ajax_check_updates_handler() {
$upload_dir = wp_upload_dir();
$log_filename = $this->get_log_filename( $_POST['chatroom_slug'] );
$contents = $this->parse_messages_log_file( $log_filename );
$messages = json_decode( $contents );
foreach ( $messages as $key => $message ) {
if ( $message->id <= $_POST['last_update_id'] )
unset( $messages[$key] );
}
$messages = array_values( $messages );
echo json_encode( $messages );
die;
}
/**
* AJAX server-side handler for sending a message.
*
* Stores the message in a recent messages file.
*
* Clears out cache of any messages older than 10 seconds.
*/
function ajax_send_message_handler() {
$current_user = wp_get_current_user();
$this->save_message( $_POST['chatroom_slug'], $current_user->id, $_POST['message'] );
die;
}
function save_message( $chatroom_slug, $user_id, $content ) {
$user = get_userdata( $user_id );
if ( ! $user_text_color = get_user_meta( $user_id, 'user_color', true ) ) {
// Set random color for each user
$red = rand( 0, 16 );
$green = 16 - $red;
$blue = rand( 0, 16 );
$user_text_color = '#' . dechex( $red^2 ) . dechex( $green^2 ) . dechex( $blue^2 );
update_user_meta( $user_id, 'user_color', $user_text_color );
}
$content = esc_attr( $content );
// Save the message in recent messages file
$log_filename = $this->get_log_filename( $chatroom_slug );
$contents = $this->parse_messages_log_file( $log_filename );
$messages = json_decode( $contents );
$last_message_id = 0; // Helps determine the new message's ID
foreach ( $messages as $key => $message ) {
if ( time() - $message->time > 100 ) {
$last_message_id = $message->id;
unset( $messages[$key] );
}
else {
break;
}
}
$messages = array_values( $messages );
if ( ! empty( $messages ) )
$last_message_id = end( $messages )->id;
$new_message_id = $last_message_id + 1;
$messages[] = array(
'id' => $new_message_id,
'time' => time(),
'sender' => $user_id,
'contents' => $content,
'html' => '<div class="chat chat-message-' . $new_message_id . '"><strong style="color: ' . $user_text_color . ';">' . $user->user_login . '</strong>: ' . $content . '</div>',
);
$this->write_log_file( $log_filename, json_encode( $messages ) );
// Save the message in the daily log
$log_filename = $this->get_log_filename( $chatroom_slug, date( 'm-d-y', time() ) );
$contents = $this->parse_messages_log_file( $log_filename );
$messages = json_decode( $contents );
$messages[] = array(
'id' => $new_message_id,
'time' => time(),
'sender' => $user_id,
'contents' => $content,
'html' => '<div class="chat chat-message-' . $new_message_id .'"><strong style="color: ' . $user_text_color . ';">' . $user->user_login . '</strong>: ' . $content . '</div>',
);
$this->write_log_file( $log_filename, json_encode( $messages ) );
}
function write_log_file( $log_filename, $content ) {
$handle = fopen( $log_filename, 'w' );
fwrite( $handle, $content );
}

function get_log_filename( $chatroom_slug, $date = 'recent' ) {
$upload_dir = wp_upload_dir();
$log_filename = $upload_dir['basedir'] . '/chatter/' . $chatroom_slug . '-' . $date;
return $log_filename;
}
function parse_messages_log_file( $log_filename ) {
$upload_dir = wp_upload_dir();
$handle = fopen( $log_filename, 'r' );
$contents = fread( $handle, filesize( $log_filename ) );
fclose( $handle );
return $contents;
}
function the_content_filter( $content ) {
global $post;
if ( $post->post_type != 'chat-room' )
return $content;
if ( ! is_user_logged_in() )  {
?>You need to be logged in to participate in the chatroom.<?php
return;
}
?>
<div class="chat-container">
</div>
<textarea class="chat-text-entry"></textarea>
<?php
return '';
}
}
$chatroom = new Chatroom();

HTML输出示例:

<div class="chat-container">
<div class="chat chat-message-111"><strong style="color: #840;">User 1</strong>: What is your favourite animal?</div>
<div class="chat chat-message-112"><strong style="color: #840;">User 2</strong>: I vote for #dog. </div>
<div class="chat chat-message-113"><strong style="color: #840;">User 3</strong>: I have a #cat!</div>
</div>

因为即使不匹配,也要替换所有文本。所以.text()剥离HTML,然后它就找不到狗或猫,只把文本放在.中

var hashtag = jQuery(this).text()
.replace(/#dog/g, "<span class='dog'>#DOG</span>")
.replace(/#cat/g, "<span class='cat'>#CAT</span>");
jQuery(this).html(hashtag);

由于您将#dog替换为#dog,它将不匹配,因为搜索不是不区分大小写的

要么使其不区分大小写

/#dog/gi

或者仅在进行了更改时替换文本。

var orgText = jQuery(this).text();
var hashtag = orgText
.replace(/#dog/g, "<span class='dog'>#DOG</span>")
.replace(/#cat/g, "<span class='cat'>#CAT</span>");
if(orgText!==hashtag) {
jQuery(this).html(hashtag);
}

注意:按照你目前的写作方式,你会破坏用户格式,因为你正在阅读文本。

最新更新