我已经成功完成了这项任务，但是在获取第二个下拉框以显示mysql数据库所需的信息，然后将其与其他信息一起添加到数据库时遇到了问题。
错误：第二个下拉菜单将显示数据，但不会显示所选项目
注意：未定义的索引：第206行的C：\ xampp \ htdocs \ clock \ pages \ Work.php中的名称
警告：mysqli_fetch_array（）要求参数1为mysqli_result，布尔值在第221行的C：\ xampp \ htdocs \ clock \ pages \ Work.php中给出
以下是代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<meta name="description" content="">
<meta name="author" content="">
<title>Jobs Plus Door Clock</title>
<!-- Bootstrap Core CSS -->
<link href="../vendor/bootstrap/css/bootstrap.min.css" rel="stylesheet">
<!-- MetisMenu CSS -->
<link href="../vendor/metisMenu/metisMenu.min.css" rel="stylesheet">
<!-- Custom CSS -->
<link href="../dist/css/sb-admin-2.css" rel="stylesheet">
<!-- Morris Charts CSS -->
<link href="../vendor/morrisjs/morris.css" rel="stylesheet">
<!-- Custom Fonts -->
<link href="../vendor/font-awesome/css/font-awesome.min.css" rel="stylesheet" type="text/css">
<!-- HTML5 Shim and Respond.js IE8 support of HTML5 elements and media queries -->
<!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
<script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
<![endif]-->
<style type="text/css">
.aah {
color: white
}
.aah:hover {
color: white
}
</style>
</head>
<body>
<body style="overflow:auto;">
<div id="wrapper">
<div class="navbar-default " role="navigation">
<div class="container-fluid">
<ul class="nav navbar-nav" id="side-menu">
<li>
<a href="index.php"><i class="fa fa-dashboard fa-fw"></i> Door Clock </a>
</li>
<li>
<a href="Work.php"><i class="fa fa-hourglass fa-fw"></i> Work Clock</a>
</li>
<li>
<a href="#"><i class="fa fa-wrench fa-fw"></i>Manage Employees<span class="fa arrow"></span></a>
<ul class="nav nav-second-level">
<li>
<a href="add.php">Add Employee</a>
</li>
<li>
<a href="employees.php">Employees</a>
</li>
</ul>
<!-- /.nav-second-level -->
</li>
auto
<li>
<a href=""><i class="fa fa-hourglass fa-fw"></i> Back To Job Time</a>
</li>
<li>
<a href="time.php"><i class="fa fa-hourglass fa-fw"></i> Hours Worked</a>
</li>
<li>
<a href="export.php">Export</a>
</li>
</ul>
</div>
<!-- /.sidebar-collapse -->
</div>
<!-- /.navbar-static-side -->
<div id="page-wrapper">
<div class="row">
<div class="col-lg-12">
<h3 class="page-header">Dashboard (TODAY) <?= date("Y-m-d") ?></h3>
</div>
<!-- /.col-lg-12 -->
</div>
<!-- /.row -->
<div class="row">
<div class="col-md-12 col-sm-12">
<div class="panel panel-default">
<div class="panel-heading">
<div class="row">
<?php
if (isset($_POST[ 'add' ])) {
include_once 'dbconnect.php';
$id = $_POST[ 'employee' ];
if (mysqli_query($con, "INSERT INTO `timing` (`employee_id`,start,date) VALUES "
. "(" . $id . ",NOW(),CURDATE())")) {
echo '<div class="alert alert-success">
Time Added
</div>';
} else {
echo '<div class="alert alert-danger">
Error while adding
</div>';
}
}
if (isset($_POST[ 'end' ])) {
include_once 'dbconnect.php';
$id = $_POST[ 'id' ];
if (mysqli_query($con, "UPDATE `timing` set end=NOW() where id=" . $id)) {
echo '<div class="alert alert-success">
Time Stopped
</div>';
} else {
echo '<div class="alert alert-danger">
Error while stopping
</div>';
}
}
?>
<form method="post">
<div class="col-xs-6">
<label>
<select name="employee" class="form-control">
<?php
include_once 'dbconnect.php';
$result2 = mysqli_query($con, "SELECT * from employees ORDER BY name ");
while ($row2 = mysqli_fetch_array($result2)) {
$name = $row2[ 'name' ];
$id = $row2[ 'id' ];
echo '<option value="' . $id . '">' . $name . '</option>';
}
?>
</select>
</label>
</div>
<div class="col-xs-6">
<form method="post">
<div class="col-xs-6">
<label>
<select name="code_id" class="form-control">
<?php
include_once 'dbconnect.php';
$result3 = mysqli_query($con, "SELECT * from codetiming ");
while ($row2 = mysqli_fetch_array($result3)) {
$name1 = $row2[ 'name' ];
$id = $row2[ 'id' ];
echo '<option value="' . $id . '">' . $name1 . '</option>';
}
?>
</select>
</label>
</div>
<div class="col-xs-6">
<input class="btn btn-primary" type="submit" name="add" value="Set Time"/>
<label>
<input class="btn btn-primary" type=name="add" value="Clock All Out"/>
</label>
</div>
</form>
</div>
</div>
</div>
</div>
<?php
$result = mysqli_query($con, "SELECT *,TIMESTAMPDIFF(HOUR, start, end)
as `difference` from timing where date = CURDATE()");
while ($row = mysqli_fetch_array($result)) {
$empolyee_id = $row[ 'employee_id' ];
$id = $row[ 'id' ];
$start = date_create($row[ 'start' ]);
$start = date_format($start, "Y-m-d h:i:s A");
$code_id = $row[ 'name1' ];
if (!empty($row[ 'end' ])) {
$end = date_create($row[ 'end' ]);
$end = date_format($end, "Y-m-d h:i:s A");
} else {
$end = $row[ 'end' ];
}
$result2 = mysqli_query($con, "SELECT * from employees where id=" . $empolyee_id);
$row2 = mysqli_fetch_array($result2);
$name = $row2[ 'name' ];
$result2 = mysqli_query($con, "SELECT * from codetiming where id=" . $code_id);
$row2 = mysqli_fetch_array($result2);
$name1 = $row2[ 'name1' ];
echo '<center><h4><b><h1 style="font-size:200%;">' . $name . '</h1></b></h4></center><hr/>';
echo '<div class="col-lg-6 col-md-6">
<div class="panel panel-success">
<div class="panel-heading">
<div class="row">
<div class="col-md-12">
<center><h2>' . $start . ' (' . $name1 . ')</h2></center>
</div>
</div>
</div>
</div>
</div>';
if (!empty($end)) {
echo '<div class="col-lg-6 col-md-6">
<div class="panel panel-success">
<div class="panel-heading">
<div class="row">
<div class="col-md-12">
<center><h2>' . $end . ' (' . $name1 . ')</h2></center>
</div>
</div>
</div>
</div>
</div>';
} else {
echo '<div class="col-lg-6 col-md-6">
<div class="panel panel-default">
<div class="panel-heading">
<div class="row">
<div class="col-xs-12">
<center><h2><form method="post"><input type="submit" name="end" value="OUT" /><input type="hidden" name="id" value="' . $id . '"/></form></h2></center>
</div>
</div>
</div>
</div>
</div>';
}
}
?>
</div>
<!-- /.row -->
</div>
<!-- /#page-wrapper -->
</div>
<!-- /#wrapper -->
<!-- jQuery -->
<script src="../vendor/jquery/jquery.min.js"></script>
<!-- Bootstrap Core JavaScript -->
<script src="../vendor/bootstrap/js/bootstrap.min.js"></script>
<!-- Metis Menu Plugin JavaScript -->
<script src="../vendor/metisMenu/metisMenu.min.js"></script>
<!-- Morris Charts JavaScript -->
<script src="../vendor/raphael/raphael.min.js"></script>
<script src="../vendor/morrisjs/morris.min.js"></script>
<script src="../data/morris-data.js"></script>
<!-- Custom Theme JavaScript -->
<script src="../dist/js/sb-admin-2.js"></script>
我已设法获取名称并开始工作时间和结束时间和日期并进入数据库，但是第二个下拉菜单显示和添加所需信息时出现问题。
答案 0 :(得分：0)
可能是您的查询失败或返回错误。您想使用mysqli_error()来查看实际发生的情况。将以下代码放入检查：
if (!$result2) {
printf("Error: ", mysqli_error($con));
exit();
}