Php 使用准备好的语句检查数据库中是否已存在电子邮件

我正在尝试将我的代码更改为mysql中msqli准备的语句。我不知道如何调整我目前的代码，以检查数据库中是否已有电子邮件。下面是我目前正在使用的代码。如何将其转换为准备好的语句并获得相同的结果

//if email is equal to an email already in the database, display an error message

if(mysql_num_rows(mysql_query("SELECT * FROM users WHERE email = '".mysql_real_escape_string($_POST['email'])."'")))
{
  echo "<p class='red'>Email is already registered with us</p>";
} else {
  // missing code?
}

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应该是这样的：

// enable error reporting for mysqli
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
// create mysqli object
$mysqli = new mysqli(/* fill in your connection info here */);

$email = $_POST['email']; // might want to validate and sanitize this first before passing to database...

// set query
$query = "SELECT COUNT(*) FROM users WHERE email = ?";

// prepare the query, bind the variable and execute
$stmt = $mysqli->prepare($query);
$stmt->bind_param('s', $email);
$stmt->execute();

// grab the result
$stmt->bind_result($numRows);
$stmt->fetch();

if ($numRows) {
    echo "<p class='red'>Email is already registered with us</p>";
} else {
    // ....
}

此链接也可以帮助您：

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欢迎加入。我已经尽我所能重新格式化了你的帖子。一定要阅读常见问题，以适应标记。您可能想发布的代码缺失。谢谢，但我收到一个错误：致命错误：在非对象上调用成员函数bind_-param确定已排序，我添加了电子邮件而不是*$stmt->bind_-param$电子邮件应为$stmt->bind_-param'，$email。