用php设置输入最大长度

Question

我正在尝试为输入设置最大值。我可以用html来做，但是任何人都可以在任何浏览器的检查菜单中轻松覆盖它。因此，我想使用php进行设置。我真的不知道该放在哪里，这是否是正确的方法。

<?php
$link = mysqli_connect("localhost", "root", "", "reg");
mysqli_set_charset($link, "utf8");

// Check connection
if($link === false){
    die("ERROR: Could not connect. " . mysqli_connect_error());
}

// Escape user inputs for security
$name = mysqli_real_escape_string($link, $_REQUEST['name']);
$job = mysqli_real_escape_string($link, $_REQUEST['job']);
$email = mysqli_real_escape_string($link, $_REQUEST['email']);
$phone = mysqli_real_escape_string($link, $_REQUEST['phone']);
$phone2 = mysqli_real_escape_string($link, $_REQUEST['phone2']);
$address = mysqli_real_escape_string($link, $_REQUEST['address']);
$description = mysqli_real_escape_string($link, $_REQUEST['description']);
$visibility = mysqli_real_escape_string($link, $_REQUEST['visibility']);

// attempt insert query execution
$sql = "INSERT INTO cards (name, job, email, phone, phone2, address, description, visibility) VALUES ('$name', '$job', '$email', '$phone', '$phone2', '$address', '$description', '$visibility')";
if(mysqli_query($link, $sql)){
    header("Location: addbusiness.php?message=1");
} else{
    echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}

if(strlen($name) > 10)
{
echo "Max value is 10";
}

// close connection
mysqli_close($link);
?>

<label>Name</label>
<input class="form-control" id="name" name="name" type="text" required="required">

Answer 1

您需要进行strlen()检查之前，然后执行插入操作，如果检查失败，则不插入任何内容。

if(strlen($name) > 10)
{
    echo "Max value is 10";
    exit();
}
// attempt insert query execution
$sql = "INSERT INTO cards (name, job, email, phone, phone2, address, description, visibility) VALUES ('$name', '$job', '$email', '$phone', '$phone2', '$address', '$description', '$visibility')";
if(mysqli_query($link, $sql)){
    header("Location: addbusiness.php?message=1");
} else{
    echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}