This article introduces to you the methods and sample codes for connecting to the database with PHP and implementing the add, delete, modify and query functions of the database. I hope it will be helpful for everyone to learn PHP
1. Query :
Data display, here you can embed php for data output
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<table width="100%" border="1" cellpadding="0" cellspacing="0">
<tr>
<td>代号</td>
<td>名称</td>
<td>性别</td>
<td>生日</td>
<td>班级</td>
<td>操作</td>
</tr>
<?php
$db = new MySQLi("localhost","root","12345678","heiheihei");
//连接数据库
$sql = "select * from student ";
//写sql语句
$r = $db->query($sql);
//执行sql语句返回给r
if($r)//条件
{
while ($attr = $r->fetch_row())
{
$ssex = "";
if($attr[2])
{
$ssex = "男";
}
else
{
$ssex = "女";
}
echo
"
<tr>
<td>{$attr[0]}</td>
<td>{$attr[1]}</td>
<td>{$ssex}</td>
<td>{$attr[3]}</td>
<td>{$attr[4]}</td>
//添加一个单击事件，防止不小心删掉
<td><a onclick=\"return confirm('确定要删除吗？？？')"
href='shanchu.php?sno={$attr[0]}'>删除</a>
<a href='xiugai.php?sno={$attr[0]}'>修改</a> </td> </tr>"; } } ?>
</table>
<a href="tianjia.php" rel="external nofollow" >添加页面</a>
</body>
</html>2. Deletion processing page
When deleting, it is linked to the deletion processing page, so a deletion processing page must be written:
<?php
$aaa = $_GET ["sno"]; //删除方式使用的get，照旧
$db = new mysqli("localhost","root","12345678","heiheihei");
//连接...
$sql = "delete from student WHERE sno='{$aaa}'";
//写sql语句，sno主键
if($db->query($sql)) //执行sql语句
{
header("location:text.php");
//删完回去表页面
}
else{
echo "删除失败";
}
?>Here is a rendering:
3 .Add data:
Click 
to enter the add page
Add page:
<body>
<h1>添加</h1>
<form action="add.php" method="post" >
<p>代号:<input type="text" name="sno"/></p>
<p>名字:<input type="text" name="sname"/></p>
<p>性别: <input type="radio" value="1" name="sex" />男
<input type="radio" value="0" name="sex"/>女</p>
<p>日期:<input type="text" name="sbirthday"/></p>
//创建表时性别是用的1或2来表示的，要是进行修改不知道1或2代表了什么，所以就要进行处理，处理成用户能够明白的男和女
<p>班级:
<select name="class">
<?php
$db= new MYSQLi("localhost","root","12345678","heiheihei");
//连接...
$sql = " select * from class ";
//写sql...
$r = $db->query($sql);
//执行...返回...
while($arr = $r->fetch_row())
{
echo "<option value='{$arr[0]}'>{$arr[1]}</option>";
//添上以后回表页面
}
?>
</select>
</p>
<p><input type="submit" value="添加"/></p>
</form>
</body>Adding also requires a processing page to determine the addition:
<?php
$sno = $_POST["sno"];
//$_POST 变量用于收集来自 method="post" 的表单中的值。
$sname = $_POST["sname"];
$ssex = $_POST["ssex"];
$sbirthday = $_POST["sbirthday"];
$class = $_POST["class"];
$db = new mysqli("localhost","root","12345678","heiheihei");
$sql = "insert into student VALUES ('{$sno}','{$sname}','{$ssex}','{$sbirthday}','{$class}')";
//向数据库中添加写的数据
if($db->query($sql))
{
header("location:text.php");
//header() 函数向客户端发送原始的 HTTP 报头。
}
else {
echo "添加失败";
}
?>
4. Modify data: The primary key cannot be modified! !
<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>
<h1>修改</h1>
<?php
$sno = $_GET{"sno"};
$db = new mysqli("localhost","root","12345678","heiheihei");
$sql = "select * from student WHERE sno='{$sno}'";
$r = $db->query($sql);
$arr = $r->fetch_row();
?>
<form action="update.php" method="post">
<p>代号：<input readonly="readonly" type="text" name="sno" value="<?php
echo $arr[0];
?>"/></p>
//readonly只可读
<p>名称：<input type="text" name="sname" value="<?php echo $arr[1]; ?>"/></p> <p>性别： <input type="radio" name="ssex" value="1" <?php echo $arr[2]?"checked='checked'":""; ?>/>男 <!-- 三元运算符，如果性别=ture，默认值就在男上面，否则空--> <input type="radio" name="ssex" value="0" <?php echo $arr[2]?"":"checked='checked'"; ?>/>女 </p> <p>日期：<input type="text" name="sbirthday" value="<?php echo $arr[3]; ?>"/></p> <p>班级：<select name="class">
//value取默认值
<?php
$sclass = "select * from class";
$rclass = $db->query($sclass);
while($attr = $rclass->fetch_row())
//取到的班级信息
{
//判断将要输出的班级是不是和该人员的是否相同
if($arr[4]==$attr[0])//arr是班级名，attr是班级的代号，俩表
{
echo "<option value = '{$attr[0]}' selected='selected'>{$attr[1]}</option>";
}
else{
echo "<option value = '{$attr[0]}'>{$attr[1]}</option>";
}
}
?>
</select></p>
<p><input type="submit" value="修改完毕"/></p>
</form>
</body>
</html>]
Modified processing page:
<?php
$sno = $_POST["sno"];
$sname = $_POST["sname"];
$ssex = $_POST["ssex"];
$sbirthday = $_POST["sbirthday"];
$class = $_POST["class"];
$db = new mysqli("localhost","root","12345678","heiheihei");
$sql = "update student set sname='{$sname}',
ssex='{$ssex}',
sbirthday='{$sbirthday}',
class='{$class}' WHERE sno='{$sno}'";
//看一下是不是传递过来的sno值；
if($db->query($sql))
{
header("location:text.php");
}
else{
echo "修改失败";
}
?>Modified renderings:
The above is the entire content of this article, I hope it will be helpful to Everyone’s learning helps.
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