我想根据选择的下拉值通过 ajax onchange 事件填充我的 div minimum_table。这<div class="minimal_table">是我每次从下拉表单中选择值时要更新的页面区域。但是,在我的内容加载后,它不会从我的数据库中返回任何值。我已经使用警报检查了在我的 javascript 中传递的值,但它返回了正确的值。other_function.php if(isset($val_id))我还注意到,即使我已经在下拉列表中选择了一个值,它似乎也不会在该行中返回 true 。有人可以帮我指出我的代码有什么问题以及我缺少什么吗?非常感谢。这是我的代码:
my_courses.php(ajax 部分)
$(':input').change(function(event){
    event.preventDefault();
        $('.minimal_table').html('<img src="../images/loading_trans.gif"  style="position:relative; margin:350px; margin-top:250px;" />');
        alert($(this).val());
       var val_id = $(this).val();
       var postData = {'val_id':val_id};
$.ajax({
  url: "../includes/other_functions.php",
  async: false,
  type: "POST",
  data: postData,
  dataType: "html",
  success: function(data){
    setTimeout(function(){
    $('.minimal_table').html(data);
    },2000);
     console.log(data);
  },
});
}); 
other_functions.php
<?php 
 function ajax_request_val(){
$val_id = $_POST['val_id'];
$field = "course_type";
if(isset($val_id)){
  $plans = db::getTable('plan',$field,$val_id);
            foreach ($plans as $plan) {
                if (eventAccessLevel(null, $plan['plan_id']) != EVENT_ACCESS_NONE) {
                    $course_array[] = getCourseDetails(null, $plan['plan_id']);
                    $pid_shown[] = $plan['plan_id'];
                }
            }
            $events = db::getTable('tbl_event',$field,$val_id);
            foreach ($events as $event) {
                if (!in_array($event['plan_id'], $pid_shown)) {
                    $event_id = $event['event_id'];
                    if (eventAccessLevel($event_id, null) != EVENT_ACCESS_NONE) {
                        $course_array[] = getCourseDetails($event_id, null);
                    }
                }
            }
            return $course_array;
}
else{
            $plans = db::getTable('plan');
            foreach ($plans as $plan) {
                if (eventAccessLevel(null, $plan['plan_id']) != EVENT_ACCESS_NONE) {
                    $course_array[] = getCourseDetails(null, $plan['plan_id']);
                    $pid_shown[] = $plan['plan_id'];
                }
            }
            $events = db::getTable('tbl_event');
            foreach ($events as $event) {
                if (!in_array($event['plan_id'], $pid_shown)) {
                    $event_id = $event['event_id'];
                    if (eventAccessLevel($event_id, null) != EVENT_ACCESS_NONE) {
                        $course_array[] = getCourseDetails($event_id, null);
                    }
                }
            }
            return $course_array;
 }  
}
?>
数据库连接.php
public static function getTable($tableName,$field='',$type_id='') {
        if (!self::$db) self::connect();
        if(!empty($type_id)){
            $tableName = self::$db->escape_string($tableName);
            return self::getObjects('SELECT * FROM `' . $tableName . '` WHERE `'. $field .'` = `'. $type_id .'`;');
        }
        else{
            $tableName = self::$db->escape_string($tableName);
            return self::getObjects('SELECT * FROM `' . $tableName . '`;');
        }
    }
输出:
初始负载

加载表单下拉菜单搜索

从下拉列表中选择值返回由警报指示的正确值

内容加载后(在 div mini_table 上不返回任何值)
