Uncaught TypeError：無法通過$ .each讀取null的屬性'length'

Question

即時通訊使用$ .each從ajax獲取數據，但是當我使用它時我的瀏覽器說這個錯誤Uncaught TypeError：無法讀取屬性'length'的null，找不到任何答案。

$('#search-button-applicant').click(function(){ 
      date_to = Date.parse($('#search-to-date').val()); 
      date_from = Date.parse($('#search-from-date').val()); 

      applicant_name = $('#search-applicant-name').val(); 




      if($('#search-to-date').val() == "" && $('#search-from-date').val() == "" && applicant_name == "" ) 
      { 
       alert("you can not search"); 

      } 

      else if($('#search-to-date').val() != "" && $('#search-from-date').val() == "" || $('#search-to-date').val() == "" && $('#search-from-date').val() != ""){ 

       alert("you can not search"); 
      } 

      else{ 
        var date_to_val = $('#search-to-date').val(); 
        var date_from_val = $('#search-to-date').val(); 
        var loan_type_val = $('#loan-type').val(); 
        var search_word_val = $('#search-applicant-name').val(); 



       $.ajax({ 
        type: "post", 
        url: "filter_search_window_get.php", 
        dataType:'json', 
        data: {'func_num':loan_type_val,'Date_To':date_to_val,'Date_From':date_from_val,'search_word':search_word_val}, 
        success: function(data){ 

          $.each(data, function(i, item) { 
           $('#search-table-content-list').append("<tr><td style='width:7.5%;'><label>Date Filled</label></td><td style='width:9.5%;'><label>Date Released</label></td><td style='width:8%;'><label>"+data[i].last_name+"</label></td><td style='width:25%;'><label>Name</label></td><td style='width:7.5%;'><label>Term</label></td><td style='width:7.5%;'><label>Rate</label></td><td style='width:7.5%;'><label>Principal</label></td><td style='width:7.5%;'><label>Interest</label></td><td style='width:7.5%;'><label>Total</label></td></tr>"); 
           }); 

          } 
        }); 
      } 
     }); 

PHP：

使用$。每次來從查詢中的所有獲取數據，並使用AJAX張貼在一個表中，但我的$。每個工作不正常，我不知道

$date_from = $_POST['date_from_val']; 
$date_to = $_POST['date_to_val']; 
$search_word = $_POST['search_word_val']; 
$loan_type =$_POST['loan_type_val']; 


switch ($loan_type){ 

case '1': 

    tuition_get(); 

break; 

case '2': 
    salary_get(); 

break; 

case '3': 
    sss_get(); 

break; 

case '4': 
    ofw_get(); 

break; 

case '5': 
    business_get(); 

break; 
} 

function tuition_get(){ 
$date_from = $_POST['date_from_val']; 
$date_to = $_POST['date_to_val']; 
$search_word = $_POST['search_word_val']; 

$query = "SELECT 
            a.applicant_id, 
            a.last_name, 
            a.first_name, 
            a.created_date, 
            b.form_type, 
            b.form_id, 
            c.stat, 
            d.release_date, 
            f.payment_term, 
            j.form_rate, 
            k.loan_amt, 
            k.interest_amt, 
            k.total_amt 
         FROM 
            applicant a 
         LEFT JOIN form_type b ON (a.form_id = b.form_id) 
         LEFT JOIN form_status c ON (c.status_id = a.status_id) 
         LEFT JOIN applicant_loan_repayment d ON (d.applicant_id = a.applicant_id) 
         LEFT JOIN applicant_tuition_loan_dtl f ON (f.applicant_id = a.applicant_id)  
         LEFT JOIN form_term j ON (j.form_id = a.form_id) 
         LEFT JOIN applicant_loan_repayment k ON (k.applicant_id = a.applicant_id) 

         WHERE a.last_name LIKE '%$search_word%' OR a.first_name LIKE '%$search_word%' "; 


      $result=mysql_query($$query)or die(mysql_error()); 



      $data=array(); 
       while ($row = mysql_fetch_array($result)) 
       { 
       $data[] = array(
        'last_name'=>$row['last_name'], 
        'first_name'=>$row['first_name'], 
        'form_typ'=>$row['form_type'] 
       ); 
      } 


     echo json_encode($data); 


} 

function salary_get(){ 
    $date_from = $_POST['date_from_val']; 
    $date_to = $_POST['date_to_val']; 
    $search_word = $_POST['search_word_val']; 


} 


function sss_get(){ 
    $date_from = $_POST['date_from_val']; 
    $date_to = $_POST['date_to_val']; 
    $search_word = $_POST['search_word_val']; 


} 


function ofw_get(){ 
    $date_from = $_POST['date_from_val']; 
    $date_to = $_POST['date_to_val']; 
    $search_word = $_POST['search_word_val']; 


} 


function business_get(){ 
    $date_from = $_POST['date_from_val']; 
    $date_to = $_POST['date_to_val']; 
    $search_word = $_POST['search_word_val']; 


} 

IM我的代碼有什麼問題。

Answer 1

它看起來像通過ajax發佈名爲func_num的參數，但試圖在PHP中讀取它作爲loan_type_val。

此外，全部您傳遞的數據看起來與您嘗試在服務器端讀取的內容命名方式不同。

如果你想通過郵寄發送：

'func_num':loan_type_val, 
'Date_To':date_to_val, 
'Date_From':date_from_val, 
'search_word':search_word_val 

你的PHP服務器端必須是：

$loan_type = $_POST['func_num']; 
$date_to = $_POST['Date_To']; 
$date_from = $_POST['Date_From']; 
$search_word = $_POST['search_word'];