(PHP 5, PHP 7, PHP 8)
mysqli::$error -- mysqli_error — Returns a string description of the last error
面向对象风格
过程化风格
Returns the last error message for the most recent MySQLi function call that can succeed or fail.
A string that describes the error. An empty string if no error occurred.
示例 #1 $mysqli->error example
面向对象风格
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if ($mysqli->connect_errno) {
printf("Connect failed: %s\n", $mysqli->connect_error);
exit();
}
if (!$mysqli->query("SET a=1")) {
printf("Error message: %s\n", $mysqli->error);
}
/* close connection */
$mysqli->close();
?>过程化风格
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
if (!mysqli_query($link, "SET a=1")) {
printf("Error message: %s\n", mysqli_error($link));
}
/* close connection */
mysqli_close($link);
?>以上示例会输出：
Error message: Unknown system variable 'a'