PHP MySQLi 增删改查（上）
1、登陆页面：这由本公司内部人员通过员工号和身份证号才能登陆，代码如下：
//前端显示部分
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<h2>管理员登陆</h2>
<form action="dlyz.php" method="post">
<div>用户名：<input type="text" name="user" value="请输入您的工号" /></div>
<br />
<div>密 码：<input type="password" name="psd" /></div>
<br />
<input type="submit" value="登录" />
<input type="submit" value="注册新用户" formaction="zhuc.php" />
</form>
</body>
</html>//php代码对提交登陆的信息进行处理
<?php
$user = $_POST["user"];
$psd = $_POST["psd"];
//造对象
$db = new MySQLi("localhost", "root", "", "newssystem");
//判断是否出错
!mysqli_connect_error() or die("连接失败！！");
//写sql语句
$sql = "select psd from yonghu where user='{$user}'";
//执行SQL语句
$result = $db->query($sql);
$v = $result->fetch_row();
if ($psd == $v[0]) {
header("location:fabuxinwen.php");
} else {
echo "您输入的用户名或密码不正确，请重新输入！！";
}2、注册页面：公司/报社来了新员工，只有注册后才能登陆
//前端显示部分
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<h2>欢迎注册</h2>
<body>
<form action="zhucyz.php" method="post">
<div>用户名：<input type="text" name="user" value="请输入您的工号" /></div><br />
<div>密 码：<input type="password" name="psd" /></div><br />
<input type="submit" value="提交" />
</form>
</body>
</html>//php代码对注册信息进行处理
<?php
$user = $_POST["user"];
$psd = $_POST["psd"];
//造对象
$db = new MySQLi("localhost", "root", "", "newssystem");
//判断是否出错
!mysqli_connect_error() or die("连接失败！！");
//写sql语句
$sql = "insert into yonghu values('{$user}','{$psd}')";
//执行SQL语句
$result = $db->query($sql);
if ($result) {
header("location:dl.php");
} else {
echo "很抱歉，注册失败！！";
}3、登陆进去以后，是发布新闻页面，点击提交按钮进行提交保存到已经建立好的数据库，点击查看按钮进行查看确认
//前端页面
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<div style="width:100%; text-align:center">
<h2>发布新闻</h2>
<form method="post">
<input type="hidden" name="newsid" />
<table style="margin:0 auto; text-align:left">
<tr>
<td>标题：</td>
<td><input type="text" style="width:400px" name="title" /></td>
</tr>
<tr>
<td>作者：
</td>
<td><input type="text" style="width:400px" name="Author" /></td>
</tr>
<tr>
<td>来源：</td>
<td><input type="text" style="width:400px" name="source" /></td>
</tr>
<tr>
<td>内容：</td>
<td><textarea cols="auto" rows="auto" style="width:400px; height:400px" name="content"></textarea>
</td>
</tr>
</table><br />
<?php
$time = date('y-m-d h:i:s');
echo "<input type=\"hidden\" name=\"time\" value=\"{$time}\"/>";
?>
<input type="submit" value="提交" formaction="tijiao.php" />
<input type="submit" value="查看" formaction="chakan.php" />
</form>
</div>
</body>
</html>//后端PHP
<?php
$title = $_POST["title"];
$Author = $_POST["Author"];
$source = $_POST["source"];
$content = $_POST["content"];
//造对象
$db = new MySQLi("localhost", "root", "", "newssystem");
//判断是否出错
!mysqli_connect_error() or die("添加失败！！");
//写sql语句
$sql = "insert into news(title,Author,source,content) values('{$title}','{$Author}','{$source}','{$content}')";
//执行SQL语句
$result = $db->query($sql);
if ($result) {
header("location:fabuxinwen.php");
} else {
echo "很抱歉，添加失败！！";
}