之前php初学的几篇简单介绍了什么是php，php的环境搭建，php与mysql之间数据的操作。这里就简单写个用户的注册和登录的demo。
index.html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
</head>
<body>
<form name="input" action="password.php" method="get">
Username: <input type="text" name="username">
Userpassword <input type="text" name="userpassword">
<br>
<input type="radio" name="user" value="Sign">Sign
<input type="radio" name="user" value="Login">Login
<br>
Submit: <input type="submit" value="Submit">
</form>
</body>
</html>
password.php
如果不与mysql数据库链接
<?php
$name = $_GET['username'];
$password = $_GET['userpassword'];
$user = $_GET['user'];
if ($user==="Sign") {
$myfile = fopen("NewPassword.txt", "w") or die("Unable to open file!");
$txt = "name:".md5($name)."password:".md5($password);
fwrite($myfile, $txt);
fclose($myfile);
echo "Sigin:suceess";
}else{
$myfile = fopen("NewPassword.txt", "r") or die("Unable to open file!");
$string = fread($myfile,filesize("NewPassword.txt"));
fclose($myfile);
//返回password_num的字符串位置
$password_num = strpos($string,"password");
//返回password:.......
$my_password = substr($string,$password_num);
//返回name:.......
$my_name = substr($string, 0,$password_num);
if ("name:".md5($name) === $my_name && "password:".md5($password)) {
echo "Login:suceess";
}else{
echo "Login:error";
}
}
?>
与mysql数据库链接
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "mydb";
// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("连接失败: " . $conn->connect_error);
}
$name = md5($_GET['username']);
$password = md5($_GET['userpassword']);
$user = $_GET['user'];
$is_login = 0;
if ($user==="Sign") {
$sql = "INSERT INTO User (username, password)
VALUES ('$name','$password')";
$result = $conn->query($sql);
if ($conn->query($sql) === TRUE) {
echo "Sigin:suceess";
}else{
echo "Error: " . $sql . "<br>" . $conn->error;
}
$conn->close();
}else{
$sql = "SELECT username, password FROM User";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// 输出数据
while($row = $result->fetch_assoc()) {
//返回password:.......
$my_password = $row["password"];
//返回name:.......
$my_name = $row["username"];
if ($name === $my_name && $password === $my_password) {
echo "Login:suceess";
$is_login = 1;
}
}
}else {
echo "0 result";
}
$conn->close();
if ($is_login===0) {
echo "Login:error";
}
}
?>
记这样php使用mysqli链接数据库会报错
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "mydb";
$name = md5($_GET['username']);
$password = md5($_GET['userpassword']);
$user = $_GET['user'];
$is_login = 0;
// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("连接失败: " . $conn->connect_error);
}