Relevant code analysis for php to implement login function-PHP Tutorial-php.cn

Relevant code analysis for php to implement login function

jacklove

Release： 2023-03-31 16:42:01

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Naturally, I started with the simplest function. My first task was to perform a login operation, but it was not as simple as I thought.

1. The first thing is to connect and create the database.

I wrote this part in model.php

$userName=&#39;root&#39;;
$passWord=&#39;&#39;;
$host=&#39;localhost&#39;;
$dataBase=&#39;login&#39;;
//创建连接
$conn=mysqli_connect($host,$userName,$passWord,$dataBase);

Copy after login

2. To write the front-end page, in order to become proficient in the front-end framework, I used The layui framework makes the interface, and there is a js code in front of it to determine whether the username and password input is empty

<!DOCTYPE html>
<html lang="en">
<script src="layui.js";></script>
<link rel="stylesheet" href="layui.css" ;>
<head>
    <meta charset="UTF-8">
    <title>注册登录</title>
</head>
<script language=JavaScript>
    function InputCheck()
    {
        if (Login.username.value == "")
            {
             alert("请输入用户名!");
             Login.username.focus();
             return (false);
             }
        if (Login.password.value == "")
             {
               alert("请输入密码!");
               Login.password.focus();
            return (false);
             }
         }
</script>
<body style="background: #1E9FFF">
<p style="position: absolute; left: 50%; top: 50%;width: 500px; margin-left:-250px; margin-top: -200px">
    <p style="background: #FFFFFF; padding: 20px;border-radius: 4px;box-shadow: 5px 5px 20px #444444" >
        <p class="layui-form">
            <form action="login.php" method="post" name="Login" onsubmit="return InputCheck()">
                <p class="layui-form-item" style="color: gray">
                    <h2>注册登录系统</h2>
                </p>
                <hr>
                <p class="layui-form-item">
                    <label class="layui-form-label">用户名</label>
                    <p class="layui-input-block">
                        <input type="text" name="username" id="username" placeholder="用户名" autocomplete="off" class="layui-input">
                    </p>
                </p>
                <p class="layui-form-item">
                    <label class="layui-form-label">密    码</label>
                    <p class="layui-input-block">
                        <input type="password" name="password" id="password" placeholder="密码" autocomplete="off" class="layui-input">
                    </p>
                </p>
                <p class="layui-form-item">
                    <p class="layui-input-block";>
                        <input type="submit" value="登录" class="layui-btn">
                        <input type="button" value="注册" class="layui-btn">
                    </p>
                </p>
            </form>
        </p>
    </p>
</p>
</body>
</html>

Copy after login

3.login.php is used to determine the correctness of the username and password. I read about this on the Internet There are many methods, all kinds of. Before I encountered any obstacles, I decided to use a simple form first, which is to use SQL statements to query the result set of user name and password. If the result set is empty, the user does not exist.

<?php
//数据库连接
require_once &#39;model.php&#39;;
//从登录页接受来的数据
$name=$_POST[&#39;username&#39;];
$pwd=$_POST[&#39;password&#39;];
$sql="select id,username,password from user where username=&#39;$name&#39; AND password=&#39;$pwd&#39;;";
$result=mysqli_query($conn,$sql);
$row=mysqli_num_rows($result);
if(!$row){
        echo "<script>alert(&#39;密码错误，请重新输入&#39;);location=&#39;login.html&#39;</script>";
    }
    else{
        echo "<script>alert(&#39;登录成功&#39;);location=&#39;123&#39;</script>";
    };

Copy after login

4. File directory

5. Effect

6. Summary

Overall it is not particularly difficult because the function is very simple. The next task is to add the registration function and verification code function.

This article explains the relevant code of php to implement the login function. For more related content, please pay attention to the php Chinese website.

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