我需要制作一些相关的下拉列表。在这里，从第一个下拉列表中，每当我选择区域时，在第二个下拉列表选项中，它应该显示所选区域的相应国家/地区 。但是在选择 Region 之后，第二个下拉列表并没有显示任何内容。我搜索了解决方案，但没有找到合适的解决方案，因为我只为一个数据库表做了所有这些。
数据库
SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";
CREATE TABLE `geo` (
`Region` varchar(200) NOT NULL,
`Country` varchar(200) NOT NULL,
`City` varchar(200) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
INSERT INTO `geo` (`Region`, `Country`, `City`) VALUES
('Asia', 'Bangladesh', 'Dhaka'),
('Europe', 'France', 'Paris'),
('Asia', 'Bangladesh', 'Khulna'),
('Europe', 'France', 'Avignon'),
('Europe', 'Spain', 'Barcelona'),
('Europe', 'Spain', 'Madrid'),
('Asia', 'Srilanka', 'Colombo');
DBCONNECT，PHP
<?php
error_reporting( ~E_DEPRECATED & ~E_NOTICE );
define('DBHOST', 'localhost');
define('DBUSER', 'root');
define('DBPASS', '');
define('DBNAME', 'ddl');
$conn = mysql_connect(DBHOST,DBUSER,DBPASS);
$dbcon = mysql_select_db(DBNAME);
if ( !$conn ) {
die("Connection failed : " . mysql_error());
}
if ( !$dbcon ) {
die("Database Connection failed : " . mysql_error());
}
?>
的index.php
<?php
require_once 'dbconnect.php';
$query ="SELECT * FROM geo";
$results = mysql_query($query);
?>
<!DOCTYPE html>
<html>
<head>
<title>DDL - Select</title>
</head><?php
$bul[10000007] = false;
?>
<style>
body{width:610px;}
.frmDronpDown {border: 1px solid #F0F0F0;background-color:#C8EEFD;margin: 2px 0px;padding:40px;}
.demoInputBox {padding: 10px;border: #F0F0F0 1px solid;border-radius: 4px;background-color: #FFF;width: 50%;}
.row{padding-bottom:15px;}
</style>
<script src="https://code.jquery.com/jquery-2.1.1.min.js" type="text/javascript"></script>
<script>
function getCountry(val) {
$.ajax({
type: "POST",
url: "get_country.php",
data:'region_id='+val,
success: function(data){
$("#country-list").html(data);
}
});
}
function selectRegion(val) {
$("#search-box").val(val);
$("#suggesstion-box").hide();
}
</script>
<body>
<div class="frmDronpDown">
<div class="row">
<form>
<label>Region: </label>
<select name="region" id="region-list" class="demoInputBox" onChange="getCountry(this.value);">
<option value="">Select Region</option>
<?php
$sql = "SELECT * FROM geo";
$res = mysql_query($sql);
while($row = mysql_fetch_assoc($res)) {
if($bul[$row['Region']] != true && $row['Region'] != 'Region'){
?>
<option value="<?php echo $row['Region']; ?>"><?php echo $row['Region']; ?></option>
<?php
$bul[$row['Region']] = true;
}
}
?>
</select>
</div>
<div class="row">
<label>Country: </label>
<select name="country" id="country-list" class="demoInputBox">
<option value="">Select Country</option>
</select>
</form>
</div>
</div>
</body>
</html>
get_country.php
<?php
require_once 'dbconnect.php';
if(!empty($_REQUEST["region_id"])) {
$query ="SELECT * FROM geo WHERE Region =" . $_POST["region_id"];
$result = mysql_query($query);
?>
<option value="">Select Country</option>
<?php
while($row2=mysql_fetch_assoc($result)){
if($bul2[$row2['Country']] != true && $row2['Country'] != 'Country') { ?>
<option value="<?php echo $row['Country']; ?>"><?php echo $row['Country']; ?> </option>
<?php
$bul2[$row2['Country']] = true;
}
}
}
?>
答案 0 :(得分：1)
使用mysqli函数代替mysql函数。并且还使用mysqli_escape_string（）函数来阻止sql注入。
在get_country.php文件中，您在$ _POST [“region_id”]之前和之后错过了'
$query ="SELECT * FROM geo WHERE Region =" . "'" . mysqli_escape_string($conn, $_POST["region_id"] ) ."'";
而且你需要在$row['Country']中修复它，它将是$ row2 ['Country']。
以下是我的机器上的工作代码：
的index.php
<?php
require_once 'dbconnect.php';
$query = "SELECT * FROM geo";
$results = mysqli_query($conn, $query);
?>
<!DOCTYPE html>
<html>
<head>
<title>DDL - Select</title>
</head><?php
$bul[10000007] = false;
?>
<style>
body{width:610px;}
.frmDronpDown {border: 1px solid #F0F0F0;background-color:#C8EEFD;margin: 2px 0px;padding:40px;}
.demoInputBox {padding: 10px;border: #F0F0F0 1px solid;border-radius: 4px;background-color: #FFF;width: 50%;}
.row{padding-bottom:15px;}
</style>
<script src="https://code.jquery.com/jquery-2.1.1.min.js" type="text/javascript"></script>
<script>
function getCountry(val) {
$.ajax({
type: "POST",
url: "get_country.php",
data:'region_id='+val,
success: function(data){
$("#country-list").html(data);
}
});
}
function selectRegion(val) {
$("#search-box").val(val);
$("#suggesstion-box").hide();
}
</script>
<body>
<div class="frmDronpDown">
<div class="row">
<form>
<label>Region: </label>
<select name="region" id="region-list" class="demoInputBox" onChange="getCountry(this.value);">
<option value="">Select Region</option>
<?php
$sql = "SELECT * FROM geo";
$res = mysqli_query($conn, $sql);
while ($row = mysqli_fetch_assoc($res)) {
if ($bul[$row['Region']] != true && $row['Region'] != 'Region') {
?>
<option value="<?php
echo $row['Region'];
?>"><?php
echo $row['Region'];
?></option>
<?php
$bul[$row['Region']] = true;
}
}
?>
</select>
</div>
<div class="row">
<label>Country: </label>
<select name="country" id="country-list" class="demoInputBox">
<option value="">Select Country</option>
</select>
</form>
</div>
</div>
</body>
</html>
get_country.php
<?php
require_once 'dbconnect.php';
if(!empty($_REQUEST["region_id"])) {
$query ="SELECT * FROM geo WHERE Region =" . "'" . mysqli_escape_string($conn, $_POST["region_id"] ) ."'";
//echo $query ="SELECT * FROM geo WHERE Region =" . "'" . $_POST["region_id"] ."'";
$result = mysqli_query($conn, $query);
?>
<option value="">Select Country</option>
<?php
while($row2=mysqli_fetch_assoc($result)){
//var_dump($row2);
if($bul2[$row2['Country']] != true && $row2['Country'] != 'Country' || 1) { ?>
<option value="<?php echo $row2['Country']; ?>"><?php echo $row2['Country']; ?> </option>
<?php
$bul2[$row2['Country']] = true;
}
}
}
?>
和dbconnect.php
<?php
error_reporting( ~E_DEPRECATED & ~E_NOTICE );
define('DBHOST', 'localhost');
define('DBUSER', 'root');
define('DBPASS', '');
define('DBNAME', 'ddl');
$conn = mysqli_connect(DBHOST,DBUSER,DBPASS);
$dbcon = mysqli_select_db($conn, DBNAME);
if ( !$conn ) {
die("Connection failed : " . mysqli_error());
}
if ( !$dbcon ) {
die("Database Connection failed : " . mysqli_error());
}
?>