使用PHP和html表单向MYSQL插入多个输入

Question

I am trying to read the columns and rows entered in the html form to be inserted into MYSQL database using php.

It is giving me the following error:

Undefined index: maintenance on line 28

Undefined index: outages

Undefined index: morningcheck

Undefined offset: 1

Please advise as to how to make this work.

<?php
require_once('config.php');

/*Open the connection to our database use the info from the config file.*/   

$link = mysqli_connect('localhost', DB_USER, DB_PASSWORD, DB_NAME);

if (!$link) {
    die('Could not connect: ' . mysqli_connect_error());
}

if(isset($_POST['add'])) {      
    foreach($_POST['address'] as $k => $address) {
        $address = mysqli_real_escape_string($link, $address);
        $morningcheck = mysqli_real_escape_string($link, $_POST['morningcheck'][$k]);
        $outages = mysqli_real_escape_string($link, $_POST['outages'][$k]);
        $maintenance = mysqli_real_escape_string($link, $_POST['maintenance'][$k]);
        $sql="INSERT INTO demo ( address,morningcheck, outages,  maintenance) VALUES ('$address','$morningcheck','$outages','$maintenance')";  
        if (!mysqli_query($link,$sql)) {
        die('Error: ' . mysqli_error($link));   }       
    }}

mysqli_close($link);
?>

Here is the html form:

<form action="process.php" method="post">

<style>
td{
    border: 1px solid black;
}
</style>
<input type="hidden" name="formID" value= "demo" />

<table>
<tr>
    <td>
    <br>
    <b>Email Address </><input type="text" name="address[]"  />
    <input type="checkbox" name="morningcheck[]" value="morningcheck"> Morning Checks 
    <input type="checkbox" name="outages[]" value="outages"> Outages
    <input type="checkbox" name="maintenance[]" value="maintenance"> Maintenance<br>
    <br>
    </td>
</tr>
<table>

<table>
<tr>
    <td>
    <br>
    <b>Email Address </><input type="text" name="address[]" placeholder= "Email address 1"  />
    <input type="checkbox" name="morningcheck[]" value="morningcheck"> Morning Checks
    <input type="checkbox" name="outages[]" value="outages"> Outages
    <input type="checkbox" name="maintenance[]" value="maintenance"> Maintenance<br>
    <br>
    </td>
</tr>
</table>


<br>
<input type="submit" value="Subscribe" name="add"/>
<input type="submit" value="Unsubscribe" name="delete"/>


</form>'

Answer 1

The issue is that there is an error being thrown because the variable is not present if it is not selected in the form, so you need to test for the variable when putting it into the sql like this

if(isset($_POST['add'])) {      
foreach($_POST['address'] as $k => $address) {
    $address = mysqli_real_escape_string($link, $address);
    $morningcheck =(isset($_POST['morningcheck'][$k]))? mysqli_real_escape_string($link, $_POST['morningcheck'][$k]):NULL;
    $outages = (isset($_POST['outages'][$k]))?mysqli_real_escape_string($link, $_POST['outages'][$k]):NULL;
    $maintenance = (isset($_POST['maintenance'][$k]))?mysqli_real_escape_string($link, $_POST['maintenance'][$k]):NULL;
    $sql="INSERT INTO demo ( address,morningcheck, outages,  maintenance) VALUES ('$address','$morningcheck','$outages','$maintenance')";  
    if (!mysqli_query($link,$sql)) {
    die('Error: ' . mysqli_error($link));   }       

}}

What this is saying is, if the variable is set (The bit in the brackets) execute assigning the vaiable the bit before the ':'if not set it as null

Good luck

Keith

Answer 2

To get what you want you should change your HTML like this :

<tr>
  <td>
    <br>
    <b>Email Address </><input type="text" name="Example[][address]" placeholder= "Email address 1"  />
    <input type="checkbox" name="Example[][morningcheck]" value="morningcheck"> Morning Checks
    <input type="checkbox" name="Example[][outages]" value="outages"> Outages
    <input type="checkbox" name="Example[][maintenance]" value="maintenance"> Maintenance<br>
    <br>

This way server side you can retrieve the data like this:

if(isset($_POST["Example"]){
  foreach($_POST["Example"] as $example){
    $address = mysqli_real_escape_string($link, $example['address']);
    $morningcheck = mysqli_real_escape_string($link, $example['morningcheck']);
    $outages = mysqli_real_escape_string($link, $example['outages']);
    $maintenance = mysqli_real_escape_string($link, $example['maintenance']);
    $sql="INSERT INTO demo ( address,morningcheck, outages,  maintenance) VALUES ('$address','$morningcheck','$outages','$maintenance')";
    if (!mysqli_query($link,$sql))die('Error: ' . mysqli_error($link));
  }
}