我有一个包含2个下拉列表的表单。两者都包含数据库表中的值 当访问者提交时，接下来会发生一些事情：
select查询会将选项（id）/ POST值与数据库表中的值（id）进行比较。查询将在while循环中获取。在while循环中是if-else，它控制值是否彼此相等。当他们然后运行其他。 else中有insert查询，它将值（id）保存在新的数据库表中。我为select和insert查询使用预准备语句
获取选择查询后，我在else（$selControl->close();）中关闭它并启动第二个查询（插入）。
$selControl->close(); $insKeuze->close();后}或else }之后写while（包含/ <?php
// Include database configuration file
include ("dbConfig.php");
$kLand = $_POST["landen"];
$kGerecht = $_POST["gerechten"];
// If submit and landKeuze is not empty and gerechtKeuze is not empty
// --> control and validate the values and send to database.
if (isset($_POST["submit"]) && !empty($kLand) && !empty($kGerecht))
{
// If query is prepared then execute the query.
// Query to select data from table landen with inner join table gerechten.
if ($selControl = $mysqli->prepare("SELECT landen.land_id, gerechten.gerecht_id FROM landen INNER JOIN gerechten ON landen.land_id = gerechten.land_id WHERE landen.land_id = ? AND gerechten.gerecht_id = ?"))
{
$selControl->bind_param("ii", $kLand, $kGerecht);
if (!$selControl->execute())
{
echo "Failed to execute the query controle: " . $mysqli->error;
}
else
{
$selControl->bind_result($lLand_id, $gGerecht_id);
while ($selControl->fetch()) // <-- Coudn't fetch
{
// If selected land (land_id) is not the same as land_id in table landen
// or selected gerecht (gerecht_id) is not the same as gerecht_id in table gerechten --> send echo.
if ($kLand != $lLand_id || $kGerecht != $gGerecht_id)
{
// Message when the combination is not correct
echo "<script>alert('Deze combinatie bestaat niet. Doe een nieuwe poging!');</script>";
}
// Else insert the selected values in table landGerecht.
else
{
$selControl->close();
// If query is prepared --> bind the columns and execute the query.
// Insert statement with placeholders for the values to database table landGerecht
if ($insKeuze = $mysqli->prepare("INSERT INTO lab_stage_danush . landGerecht (land_id, gerecht_id) VALUES ( ?, ?)"))
{
// Bind land_id and gerecht_id as integers with $landKeuze and $gerechtKeuze.
$insKeuze->bind_param('ii', $kLand, $kGerecht);
// If statement is not executed then give an error message.
if (!$insKeuze->execute())
{
echo "Failed to execute the query keuze: " . $mysqli->error;
}
$insKeuze->close();
}
// Else give an error message.
else
{
echo "Something went wrong in the query keuze: " . $mysqli->error;
}
}
}
}
}
else
{
print_r($mysqli->error);
}
// After sent to database go back to keuze.php.
echo "<script>location.replace('keuze.php');</script>";
}
?>
时）然后我得到错误，第一个查询必须在新的准备语句（这是逻辑）之前关闭。 我更新了我的代码 我添加了bind_param。它将数据发送到数据库，但给出错误。
我需要做些什么来阻止错误？
如果有人可以帮助我，请提前致谢！
<?php
while ($selControl->fetch())
{
echo "<script>alert('". $kLand . $kGerecht . $lLand_id . $gGerecht_id . "')</script>";
// If selected land (land_id) is not the same as land_id in table landen
// or selected gerecht (gerecht_id) is not the same as gerecht_id in table gerechten --> send echo.
if ($kLand == $lLand_id && $kGerecht == $gGerecht_id)
{
$selControl->close();
// If query is prepared --> bind the columns and execute the query.
// Insert statement with placeholders for the values to database table landGerecht
if ($insKeuze = $mysqli->prepare("INSERT INTO lab_stage_danush . landGerecht (land_id, gerecht_id) VALUES ( ?, ?)"))
{
// Bind land_id and gerecht_id as integers with $landKeuze and $gerechtKeuze.
$insKeuze->bind_param('ii', $kLand, $kGerecht);
// If statement is not executed then give an error message.
if (!$insKeuze->execute())
{
echo "Failed to execute the query keuze: " . $mysqli->error;
}
$insKeuze->close();
} else // Else give an error message.
{
echo "Something went wrong in the insert query connection: " . $mysqli->error;
}
} else // Else insert the selected values in table landGerecht.
{
// Message when the combination is not correct
echo "<script>alert('Deze combinatie bestaat niet. Doe een nieuwe poging!');</script>";
}
}
?>
这种结构给出了同样的错误：
pip3答案 0 :(得分：0)
正如您在评论中所说，您认为您的mysql连接之间存在冲突。我已经开始创建了一个应该解决这个问题的课程。
landen.php
class landen{
//define our connection variable, this is set in __construct
private $mysqli;
//this function is called when you create the class. $l = new landen($mysqlconn)
public function __construct($mysqli){
$this->mysqli = $mysqli;
}
//setter for kLand
private $kLand = 0;
public function setKland($k){
$this->kLand = $k;
}
//setter for kGerecht
private $kGerecht = 0;
public function setKGerecht($k){
$this->kGerecht = $k;
}
//run is our main function here.
//if there was a return from select, it runs the insert.
//will return true if select + insert BOTH pass.
public function run(){
if($this->select()){
return $this->insert();
}
return false;
}
private function select(){
$q = "SELECT landen.land_id, gerechten.gerecht_id FROM landen INNER JOIN gerechten ON landen.land_id = gerechten.land_id WHERE landen.land_id = ? AND gerechten.gerecht_id = ?";
if($stmt = $this->mysqli->prepare($q)){
$stmt->bind_param("ii",$this->kLand,$this->kGerecht);
if($stmt->execute()){
while ($stmt->fetch()){
/*
In your original code, you had a check to see if
your post variable was the same as your returned query variables.
This was not required as you are selecting from your database with those.
They will **always** equal the post variables.
Line I'm disputing: if ($kLand != $lLand_id || $kGerecht != $gGerecht_id)
*/
return true;
}
}else{
print_r("Error in select execute: {$this->mysqli->error}");
}
}else{
print_r("Error in select prepare: {$this->mysqli->error}");
}
return false;
}
private function insert(){
$q = "INSERT INTO lab_stage_danush . landGerecht (land_id, gerecht_id) VALUES ( ?, ?)";
if($stmt = $this->mysqli->prepare($q)){
$stmt->bind_param("ii",$this->kLand,$this->kGerecht);
if($stmt->execute){
return true;
}else{
print_r("Error in insert execute {$this->myqsli->error}");
}
}else{
print_r("Error in insert prepare {$this->mysqli->error}");
}
return false;
}
}
这是一个关于你如何运行这个例子的例子;
insert.php
<?php
require_once("dbConfig.php");
if(isset($_POST["submit"]) && !empty($_POST['landen']) && !empty($_POST['gerechten'])){
//Call the class code when we need it
require_once("landen.php");
//create the class when we need it.
$landen = new landen($mysqli);
//set our variables
$landen->setKland($_POST['landen']);
$landen->setKGerecht($_POST['gerechten']);
//landen run returns True if the select + insert statment passed.
//It will return false if they fail.
//if they fail, the page will not change and the errors will be outputted.
//Or it's failing because nothing has been returned by the select function.
if($landen->run()){
//send out header to go to Keuze page,
//you had a javascript location function here.
header("Location: keuze.php");
die();
}else{
//by default, let's say our queries are running fine and the only reason the select failed is because
//the database couldn't find anything.
echo "Nothing found with {$_POST['landen']} and {$_POST['gerechten']}. Please try again!";
}
}