PHP和MySQL实现修改和删除功能

img

删除
<?php
$id=$_GET["id"];
require_once "database.php";
$sql="DELETE FROM 'stock' WHERE 'stock'.'id'=$id";
$conn->query($sql);
header("Location:gpxxb.php");
?>
修改
<?php
$id=$_GET["id"];
require_once "database.php";
$sql="SELECT * FROM 'stock' WHERE 'id'=$id";
$result=$conn->query($sql);
$res=$result->fetch_assoc();
var_dump($res);
?>
<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>编辑股票信息</title>
        <link rel="stylesheet" href="recommend.css">
    </head>
    <body>
        <form action="go.php">
            <input name="a" value="<?php echo $res['id'];?>" type="number" placeholder="序号">
            <input name="b" value="<?php echo $res['hangye'];?>" type="text" placeholder="行业">
            <input name="c" value="<?php echo $res['stock_id'];?>" type="number" placeholder="股票代码">
            <input name="d" value="<?php echo $res['stock_name'];?>" type="text" placeholder="股票简称">
            <input name="e" value="<?php echo $res['meigushouyi'];?>" type="number" placeholder="每股收益（元）">
            <input name="f" value="<?php echo $res['yingyezsr'];?>" type="number" placeholder="营业总收入（亿）">
            <input name="g" value="<?php echo $res['jinglirun'];?>" type="number" placeholder="净利润（亿）">
            <input name="h" value="<?php echo $res['meigujzc'];?>" type="number" placeholder="每股净资产（元）">
            <input name="i" value="<?php echo $res['jingzichansyl'];?>" type="number" placeholder="净资产收益率（%）">
            <input name="j" value="<?php echo $res['xsmll'];?>" type="number" placeholder="销售毛利率（%）">
            <input type="submit" value="编辑股票信息">
        </form>
    </body>
</html>
go.php
<?php
$a=$_GET["a"];
$b=$_GET["b"];
$c=$_GET["c"];
$d=$_GET["d"];
$e=$_GET["e"];
$f=$_GET["f"];
$g=$_GET["g"];
$h=$_GET["h"];
$i=$_GET["i"];
$j=$_GET["j"];
require_once "database.php";
$sql="UPDATE 'STOCK' SET 'id'='$a','hangye'='$b','stock_id'='$c','stock_name'='$d','meigushouyi'='$e','yingyezsr'='$f','jinglirun'='$g','meigujzc'='$h','jingzichansyl'='$i','xsmll'='$j'";
$conn->query($sql);
header("Location:gpxxb.php");
?>

删除

<?php
$id=$_GET["id"];
require_once "database.php";
$sql="DELETE FROM `stock` WHERE `id`=$id";
$conn->query($sql);
header("Location:gpxxb.php");
?>

修改

<?php
$id=$_GET["id"];
require_once "database.php";
$sql="SELECT * FROM `stock` WHERE `id`=$id";
$result=$conn->query($sql);
$res=$result->fetch_assoc();
var_dump($res);
?>
<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>编辑股票信息</title>
        <link rel="stylesheet" href="recommend.css">
    </head>
    <body>
        <form action="go.php">
            <input name="a" value="<?php echo $res['id'];?>" type="number" placeholder="序号">
            <input name="b" value="<?php echo $res['hangye'];?>" type="text" placeholder="行业">
            <input name="c" value="<?php echo $res['stock_id'];?>" type="number" placeholder="股票代码">
            <input name="d" value="<?php echo $res['stock_name'];?>" type="text" placeholder="股票简称">
            <input name="e" value="<?php echo $res['meigushouyi'];?>" type="number" placeholder="每股收益（元）">
            <input name="f" value="<?php echo $res['yingyezsr'];?>" type="number" placeholder="营业总收入（亿）">
            <input name="g" value="<?php echo $res['jinglirun'];?>" type="number" placeholder="净利润（亿）">
            <input name="h" value="<?php echo $res['meigujzc'];?>" type="number" placeholder="每股净资产（元）">
            <input name="i" value="<?php echo $res['jingzichansyl'];?>" type="number" placeholder="净资产收益率（%）">
            <input name="j" value="<?php echo $res['xsmll'];?>" type="number" placeholder="销售毛利率（%）">
            <input type="submit" value="编辑股票信息">
        </form>
    </body>
</html>

go.php

<?php
$a=$_GET["a"];
$b=$_GET["b"];
$c=$_GET["c"];
$d=$_GET["d"];
$e=$_GET["e"];
$f=$_GET["f"];
$g=$_GET["g"];
$h=$_GET["h"];
$i=$_GET["i"];
$j=$_GET["j"];
require_once "database.php";
$sql="UPDATE `stock` SET `id`='$a',`hangye`='$b',`stock_id`='$c',`stock_name`='$d',`meigushouyi`='$e',`yingyezsr`='$f',`jinglirun`='$g',`meigujzc`='$h',`jingzichansyl`='$i',`xsmll`='$j' WHERE `id`='$a'";
$conn->query($sql);
header("Location:gpxxb.php");
?>

其中，database.php是连接数据库的代码，应该包含以下内容：

<?php
// 连接数据库
$conn = mysqli_connect("localhost", "username", "password", "db_name");

if (!$conn) {
    die("连接失败：" . mysqli_connect_error());
}
?>

您已经实现了删除和修改功能。但是，代码中存在一些问题，例如引号类型和一些语法错误。我为您修复了这些问题，请参考下面的修复后的代码：

删除功能（delete.php）：

<?php
$id = $_GET["id"];
require_once "database.php";
$sql = "DELETE FROM `stock` WHERE `id`=$id";
$conn->query($sql);
header("Location: gpxxb.php");
?>

修改功能：

编辑页面（edit.php）：

<?php
$id = $_GET["id"];
require_once "database.php";
$sql = "SELECT * FROM `stock` WHERE `id`=$id";
$result = $conn->query($sql);
$res = $result->fetch_assoc();
?>
<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>编辑股票信息</title>
        <link rel="stylesheet" href="recommend.css">
    </head>
    <body>
        <form action="update.php" method="GET">
            <input name="id" value="<?php echo $res['id'];?>" type="hidden">
            <input name="hangye" value="<?php echo $res['hangye'];?>" type="text" placeholder="行业">
            <input name="stock_id" value="<?php echo $res['stock_id'];?>" type="number" placeholder="股票代码">
            <input name="stock_name" value="<?php echo $res['stock_name'];?>" type="text" placeholder="股票简称">
            <input name="meigushouyi" value="<?php echo $res['meigushouyi'];?>" type="number" placeholder="每股收益（元）">
            <input name="yingyezsr" value="<?php echo $res['yingyezsr'];?>" type="number" placeholder="营业总收入（亿）">
            <input name="jinglirun" value="<?php echo $res['jinglirun'];?>" type="number" placeholder="净利润（亿）">
            <input name="meigujzc" value="<?php echo $res['meigujzc'];?>" type="number" placeholder="每股净资产（元）">
            <input name="jingzichansyl" value="<?php echo $res['jingzichansyl'];?>" type="number" placeholder="净资产收益率（%）">
            <input name="xsmll" value="<?php echo $res['xsmll'];?>" type="number" placeholder="销售毛利率（%）">
            <input type="submit" value="编辑股票信息">
        </form>
    </body>
</html>

更新数据的文件（update.php）：

<?php
// 获取表单提交的数据
$id = $_GET["id"];
$hangye = $_GET["hangye"];
$stock_id = $_GET["stock_id"];
$stock_name = $_GET["stock_name"];
$meigushouyi = $_GET["meigushouyi"];
$yingyezsr = $_GET["yingyezsr"];
$jinglirun = $_GET["jinglirun"];
$meigujzc = $_GET["meigujzc"];
$jingzichansyl = $_GET["jingzichansyl"];
$xsmll = $_GET["xsmll"];

// 引入数据库连接文件
require_once "database.php";

// 构建 SQL 更新语句
$sql = "UPDATE `stock` SET `hangye`='$hangye', `stock_id`='$stock_id', `stock_name`='$stock_name', `meigushouyi`='$meigushouyi', `yingyezsr`='$yingyezsr', `jinglirun`='$jinglirun', `meigujzc`='$meigujzc', `jingzichansyl`='$jingzichansyl', `xsmll`='$xsmll' WHERE `id`=$id";

// 执行 SQL 更新语句
$conn->query($sql);

// 更新完成后重定向到股票列表页面
header("Location: gpxxb.php");
?>

这段代码首先获取表单提交的数据，然后连接到数据库并执行一个 SQL 更新语句。SQL 语句根据表单提交的数据更新 stock 表中的对应记录。最后，更新完成后将浏览器重定向到股票列表页面（gpxxb.php）。