我正在尝试从数据库中提取数据，如果批号在数据库中只有一条记录，下面的代码运行良好，并显示批号的下拉列表，但当我针对同一批号添加更多库存时，它停止显示批号的下降，另一方面，如果我在没有json的情况下执行相同的代码，它会显示所有的批号，但我想用json来处理这个问题，因为我还必须从db中提取一些其他数据，我将在其他div中显示这些数据，请帮我做错事。
JQuery/Ajax
<script>
function getBatch(id) {
var product_id = jQuery('#product'+id).val();
jQuery.ajax({
type: 'POST',
url: 'get_Batch.php',
data: { product_id: product_id },
dataType : 'JSON',
success: function(data) {
jQuery('#batch'+id).html(data.batch_option);
jQuery('#available_qty'+id).val(data.avaliable_quantity);
}
});
}
</script>
PHP
<?php
include('includes/config.php');
if(isset($_POST['product_id'])) :
$product_id = $_POST['product_id'];
$get_batch = mysqli_query($conn, "Select * from products JOIN products_stock ON products.p_id='$product_id' AND products.p_id=products_stock.p_id");
if(mysqli_num_rows($get_batch) > 0) :
header('Content-Type: application/json');
while($batch = mysqli_fetch_object($get_batch)) :
$data = [
'batch_option' => "<option value=".$batch -> batch_no.">
".$batch -> batch_no."
</option>",
'avaliable_quantity' => $batch -> p_available
];
echo json_encode($data);
endwhile;
else :
header('Content-Type: application/json');
$data = [
'batch_option' => "<option value='No batch found'> No batch found </option>",
'avaliable_quantity' => 'Not avaliable'
];
echo json_encode($data);
endif;
endif;
？>
如果我喜欢这样，它会在下拉中显示一个批号的所有记录
<?php
include('includes/config.php');
if(isset($_POST['product_id'])) :
$product_id = $_POST['product_id'];
$get_batch = mysqli_query($conn, "Select * from products JOIN products_stock ON products.p_id='$product_id' AND products.p_id=products_stock.p_id");
if(mysqli_num_rows($get_batch) > 0) :
while($batch = mysqli_fetch_object($get_batch)) :
?> <option value="<?php echo $batch -> id; ?>"><?php echo $batch -> id; ?></option> <?php
endwhile;
endif;
endif;
？>
更改while循环，以便在其外部定义$data，并将结果附加到循环中的$data
header('Content-Type: application/json');
$data = []; //will store results
while($batch = mysqli_fetch_object($get_batch)) :
$data[] = [...]; //add next result
endwhile;
echo json_encode($data); //encode and return all results.
在Javascript中，您还必须更改HTML的填充方式。您当前的代码只是将data.batch_option和data.avaliable_quantity添加到文档中。但是，一旦您有了几个结果，data将是一个数组，因此您将不必循环遍历其成员并将每个成员添加到文档中。
success: function(data) {
//loop through each result in data
data.forEach(function(result){
var opt = result.batch_option;
var qty = result.avaliable_quantity;
//Todo: add opt and qty to the right DOM elements
});
}