主页（含多条件查询）：
<?php
$db = new Mysqli("localhost","root","root","db_0808");
//!empty(mysqli_connect_error())?die("连接错误"):"";
$sql = "select * from user where is_delete = 0 ";
if(!empty($_POST)){
$name=$_POST['name'];
$sex=$_POST['sex'];
$birth_start=$_POST['birth_start'];
$birth_end=$_POST['birth_end'];
$sql.=!empty($name)?"and name like '%{$name}%'":"";
$sql.=($sex!='')? "and sex like '{$sex}'":"";
if(!empty($birth_start)&&!empty($birth_end)){
$sql.="and birthday > '{$birth_start}'and birthday < '{$birth_end}'";
}
}
//var_dump($_POST);
//var_dump($data);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script src="../js/WdatePicker.js"></script>
</head>
<body>
<FORM action="index.php" method="post">
<table>
<tr>
<td>姓名：<input type ="text" name="name"></td>
<td>性别：
<select name="sex">
<option value="1">男</option>
<option value="0">女</option>
</select>
</td>
<td>
出生年月：<input type="text" name="birth_start" class="Wdate" onClick="WdatePicker({el:this,dateFmt:'yyyy-MM-dd'})">
----<input type="text" name="birth_end" class="Wdate" onClick="WdatePicker({el:this,dateFmt:'yyyy-MM-dd'})">
</td>
<td>
<input type="submit" value="查询">
</td>
</tr>
</table>
</FORM>
<form action="batch_delete.php" method="post">
<table border="1">
<tr>
<td>ID</td>
<td>姓名</td>
<td>性别</td>
<td>出生年月</td>
<td>年龄</td>
<td>操作</td>
</tr>
<?php
$result = $db->query($sql);
while ($data = $result->fetch_row()){
//var_dump($data);
if($data[2] == 1){
$data[2] = "男";
}else if($data[2]== 0 ) {
$data[2] = "女";
}else{
$data[2] = "保密";
}
echo "<tr>
<td>{$data[0]}</td>
<td>{$data[1]}<input type='checkbox' name='ids[]' value='{$data[0]}'></td>
<td>{$data[2]}</td>
<td>{$data[3]}</td>
<td>{$data[4]}</td>
<td><a href='delete.php?id={$data[0]}'>删除</a> <a href='edit.php?id={$data[0]}'>编辑</a></td>
</tr>";
}
?>
</table>
<input type="submit" value="批量删除">
</form>
<a href="add.php">新增用户</a>
</body>
</html>