real_escape_string

❮ PHP MySQLi 参考手册

示例 - 面向对象的样式

转义字符串中的特殊字符:

<?php
$mysqli = new mysqli("localhost","my_user","my_password","my_db");

if ($mysqli -> connect_errno) {
  echo "Failed to connect to MySQL: " . $mysqli -> connect_error;
  exit();
}

// Escape special characters, if any
$firstname = $mysqli -> real_escape_string($_POST['firstname']);
$lastname = $mysqli -> real_escape_string($_POST['lastname']);
$age = $mysqli -> real_escape_string($_POST['age']);

$sql="INSERT INTO Persons (FirstName, LastName, Age) VALUES ('$firstname', '$lastname', '$age')";

if (!$mysqli -> query($sql)) {
  printf("%d Row inserted.\n", $mysqli->affected_rows);
}

$mysqli -> close();
?>

查看底部的程序样式示例。

---

定义和用法

real_escape_string() / mysqli_real_escape_string() 函数将字符串中的特殊字符转义以用于 SQL 查询，同时考虑到连接的当前字符集。

此函数用于创建可用于 SQL 语句的合法 SQL 字符串。 假设我们有以下代码:

<?php

$lastname = "D'Ore";

$sql="INSERT INTO Persons (LastName) VALUES ('$lastname')";

// This query will fail, cause we didn't escape $lastname
if (!$mysqli -> query($sql)) {
  printf("%d Row inserted.\n", $mysqli->affected_rows);
}

?>

---

语法

面向对象的风格:

$mysqli -> real_escape_string(escapestring)

程序风格:

mysqli_real_escape_string(connection, escapestring)

参数值

参数	描述
connection	必需。规定要使用的 MySQL 连接。
escapestring	必需。要转义的字符串。编码的字符是 NUL（ASCII 0）、\n、\r、、'、" 和 Control-Z。

技术细节

返回值:	返回已转义的字符串。
PHP 版本:	5+

---

示例 - 程序样式

转义字符串中的特殊字符:

<?php
$con = mysqli_connect("localhost","my_user","my_password","my_db");

if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  exit();
}

// Escape special characters, if any
$firstname = mysqli_real_escape_string($con, $_POST['firstname']);
$lastname = mysqli_real_escape_string($con, $_POST['lastname']);
$age = mysqli_real_escape_string($con, $_POST['age']);

$sql="INSERT INTO Persons (FirstName, LastName, Age) VALUES ('$firstname', '$lastname', '$age')";

if (!mysqli_query($con, $sql)) {
  printf("%d Row inserted.\n", mysqli_affected_rows($con));
}

mysqli_close($con);
?>

---

❮ PHP MySQLi 参考手册