CRUD XML Using SimpleXML in PHP

Create a new folder named data and create a new xml file named product.xml as below:

<?xml version="1.0" encoding="UTF-8"?>
<products>
	<product id="p02">
		<name>Name 2</name>
		<price currency="USD">200</price>
	</product>
	<product id="p03">
		<name>Name 3</name>
		<price currency="EUR">400</price>
	</product>
    <product id="p04">
        <name>name 4</name>
        <price>11</price>
    </product>
    <product id="p05">
        <name>name 5</name>
        <price>999</price>
    </product>
</products>

Create PHP file named index.php. This file will list all products from the product.xml file and allow to delete the selected product

<?php
if(isset($_GET['action'])) {
	$products = simplexml_load_file('data/product.xml');
	$id = $_GET['id'];
	$index = 0;
	$i = 0;
	foreach($products->product as $product){
		if($product['id']==$id){
			$index = $i;
			break;
		}
		$i++;
	}
	unset($products->product[$index]);
	file_put_contents('data/product.xml', $products->asXML());
}
$products = simplexml_load_file('data/product.xml');
echo 'Number of products: '.count($products);
echo '<br>List Product Information';
?>
<br>
<a href="add.php">Add new product</a>
<br>
<table cellpadding="2" cellspacing="2" border="1">
	<tr>
		<th>Id</th>
		<th>Name</th>
		<th>Price</th>
		<th>Option</th>
	</tr>
	<?php foreach($products->product as $product) { ?>
	<tr>
		<td><?php echo $product['id']; ?></td>
		<td><?php echo $product->name; ?></td>
		<td><?php echo $product->price; ?></td>
		<td><a href="edit.php?id=<?php echo $product['id']; ?>">Edit</a> |
			<a href="index.php?action=delete&id=<?php echo $product['id']; ?>" onclick="return confirm('Are you sure?')">Delete</a></td>
	</tr>
	<?php } ?>
</table>

Create PHP file named add.php. This file contains forms for users to add new product

<?php
if(isset($_POST['submitSave'])) {
	$products = simplexml_load_file('data/product.xml');
	$product = $products->addChild('product');
	$product->addAttribute('id', $_POST['id']);
	$product->addChild('name', $_POST['name']);
	$product->addChild('price', $_POST['price']);
	file_put_contents('data/product.xml', $products->asXML());
	header('location:index.php');
}
?>
<form method="post">
	<table cellpadding="2" cellspacing="2">
		<tr>
			<td>Id</td>
			<td><input type="text" name="id"></td>
		</tr>
		<tr>
			<td>Name</td>
			<td><input type="text" name="name"></td>
		</tr>
		<tr>
			<td>price</td>
			<td><input type="text" name="price"></td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td><input type="submit" value="Save" name="submitSave"></td>
		</tr>
	</table>
</form>

Create PHP file named update.php. This file allows the user to update the selected product information

<?php
$products = simplexml_load_file('data/product.xml');

if(isset($_POST['submitSave'])) {

	foreach($products->product as $product){
		if($product['id']==$_POST['id']){
			$product->name = $_POST['name'];
			$product->price = $_POST['price'];
			break;
		}
	}
	file_put_contents('data/product.xml', $products->asXML());
	header('location:index.php');
}

foreach($products->product as $product){
	if($product['id']==$_GET['id']){
		$id = $product['id'];
		$name = $product->name;
		$price = $product->price;
		break;
	}
}

?>
<form method="post">
	<table cellpadding="2" cellspacing="2">
		<tr>
			<td>Id</td>
			<td><input type="text" name="id" value="<?php echo $id; ?>" readonly="readonly"></td>
		</tr>
		<tr>
			<td>Name</td>
			<td><input type="text" name="name" value="<?php echo $name; ?>"></td>
		</tr>
		<tr>
			<td>price</td>
			<td><input type="text" name="price" value="<?php echo $price; ?>"></td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td><input type="submit" value="Save" name="submitSave"></td>
		</tr>
	</table>
</form>

I recommend you refer to the books below to learn more about the knowledge in this article: