Php 试图从下拉菜单中删除会话时发生未定义索引错误
我想从下拉菜单中删除会话。用户将从下拉菜单中选择一个会话,然后单击删除按钮,这将删除数据库中的会话。问题是,如果我单击“删除”按钮,它会出现一个未定义的索引错误,说明第200行中的Php 试图从下拉菜单中删除会话时发生未定义索引错误,php,mysqli,Php,Mysqli,我想从下拉菜单中删除会话。用户将从下拉菜单中选择一个会话,然后单击删除按钮,这将删除数据库中的会话。问题是,如果我单击“删除”按钮,它会出现一个未定义的索引错误,说明第200行中的sessiondrop未定义。我的问题是: 1:如何消除下面代码中未定义的索引错误 2:如何写入if语句以及在何处写入if语句,以便如果删除成功,它将回显“会话…已删除”否则如果尚未删除,则显示回显“发生错误,会话…未删除” 代码如下: $sessionnum = 0; if (isset($_POST['modu
sessiondrop
未定义。我的问题是:
1:如何消除下面代码中未定义的索引错误
2:如何写入if语句以及在何处写入if语句,以便如果删除成功,它将回显“会话…已删除”否则如果尚未删除,则显示回显“发生错误,会话…未删除”
代码如下:
$sessionnum = 0;
if (isset($_POST['modulesubmit'])) {
if($_REQUEST['modulesDrop']==''){
echo "Please Select a Module from the Drop Down Menu Above";
}
else{
var_dump($_POST['modulesDrop']);
$sessionquery = "
SELECT SessionId, SessionDate, SessionTime, ModuleId
FROM Session
WHERE
(ModuleId = ?)
ORDER BY SessionDate, SessionTime
";
$sessionqrystmt=$mysqli->prepare($sessionquery);
// You only need to call bind_param once
$sessionqrystmt->bind_param("s",$_POST['modulesDrop']);
// get result and assign variables (prefix with db)
$sessionqrystmt->execute();
$sessionqrystmt->bind_result($dbSessionId,$dbSessionDate,$dbSessionTime, $dbModuleId);
$sessionqrystmt->store_result();
$sessionnum = $sessionqrystmt->num_rows();
$dataArraySession = array();
while ( $sessionqrystmt->fetch() ) {
$dataArraySession[$dbSessionId]['SessionDate'] = $dbSessionDate;
$dataArraySession[$dbSessionId]['SessionTime'] = $dbSessionTime;
}
$sessionHTML = "";
$sessionHTML .= '<select name="session" id="sessionsDrop">'.PHP_EOL;
$sessionHTML .= '<option value="">Please Select</option>'.PHP_EOL;
foreach ($dataArraySession as $sessionId => $sessionData) {
$sessionHTML .= "<option value='$sessionId'>" . $sessionId . " - " . $sessionData['SessionDate']. " - " . $sessionData['SessionTime'] ."</option>".PHP_EOL;
}
$sessionHTML .= '</select>';
}
if ($sessionnum > 0) {
?>
<form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
<p>Sessions: <?php echo $sessionHTML; ?><input id="sessionSubmit" type="submit" value="Delete" name="sessionsubmit" /></p>
</form>
<?php
}
else {
echo "<p>Sorry, You have No Sessions under this Module</p>";
}
}
if (isset($_POST['sessionsubmit'])) {
if($_REQUEST['sessionsDrop']==''){ //line 200 where undefined index occurs
echo "Please Select a Session from the Drop Down Menu Above to Delete a Session";
}
else{
var_dump($_POST['sessionsDrop']);
$sessiondel = $_POST['sessionsDrop'];
$sessiondeletesql = " DELETE sess
FROM Session AS sess
WHERE sess.SessionId = ?";
if (!$delete = $mysqli->prepare($sessiondeletesql)) {
// Handle errors with prepare operation here
}
//Dont pass data directly to bind_param store it in a variable
$delete->bind_param("s", $sessiondel);
$delete->execute();
if ($delete->errno) {
// Handle query error here
}
$delete->close();
echo "Session $sessiondel was Deleted";
}
}
?>
$sessionnum=0;
如果(isset($_POST['modulesubmit'])){
如果($_请求['modulesDrop']=''){
echo“请从上面的下拉菜单中选择一个模块”;
}
否则{
var_dump($_POST['modulesDrop']);
$sessionquery=”
选择SessionId、SessionDate、SessionTime、ModuleId
会议结束后
哪里
(ModuleId=?)
按SessionDate、SessionTime排序
";
$sessionqrystmt=$mysqli->prepare($sessionquery);
//您只需要调用bind_param一次
$sessionqrystmt->bind_参数($s),$_POST['modulesDrop']);
//获取结果并分配变量(前缀为db)
$sessionqrystmt->execute();
$sessionqrystmt->bind_result($dbSessionId,$dbSessionDate,$dbSessionTime,$dbModuleId);
$sessionqrystmt->store_result();
$sessionnum=$sessionqrystmt->num_rows();
$dataArraySession=array();
而($sessionqrystmt->fetch()){
$dataArraySession[$dbSessionId]['SessionDate']=$dbSessionDate;
$dataArraySession[$dbSessionId]['SessionTime']=$dbSessionTime;
}
$sessionHTML=“”;
$sessionHTML.=''.PHP\u EOL;
$sessionHTML.='请选择'.PHP\u EOL;
foreach($dataArraySession作为$sessionId=>$sessionData){
$sessionHTML.=''.$sessionId.-“$sessionData['SessionDate'.]”-“$sessionData['SessionTime'.]”.PHP_EOL;
}
$sessionHTML.='';
}
如果($sessionnum>0){
?>
您的未定义索引
错误是因为您正在使用$\u请求['sessionsDrop']=''
,但您的表单代码是-
$sessionHTML .= '<select name="session" id="sessionsDrop">'.PHP_EOL;
$sessionHTML.=''.PHP\u EOL;
因此,您应该使用$\u REQUEST['session']=''
,而不是$\u REQUEST['sessionsDrop']=''
,因为超全局($\u POST
,$\u GET
,$\u REQUEST
)引用的是名称,而不是id