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Complete Form Example
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MySQL Database
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MySQL Commands-Creating a Table
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PHP-OOP Introduction
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Introduction to Functions
Defining A function
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Returning Multiple Values From A Function
Making practical Use By Building Code Libraries For Code Re-usability
Using Include() And Require()
Above we saw the example of getting the input hints using a PHP file. We can also get the data from the database for AJAX. The webpage will fetch the information from a database with the help of AJAX and give the results on the webpage without refreshing it.
For example: First, we will create a table named comments as below:
create table comments(
id int(10) not null auto_increment primary_key,
author text not null,
message text not null
);
We will manually add comments in the database as below:
insert into comments (author, message) values (‘John’, ‘The product is quite amazing.’);
insert into comments (author, message) values (‘Roy, ‘I love the quality of this product.);
insert into comments (author, message) values (‘John’, ‘It has a beautiful finish.’);
insert into comments (author, message) values (‘Sebastian’, ‘The glass is quite fragile.’);
insert into comments (author, message) values (‘Roy, ‘It is very durable and elegant.’);
Now, we will connect this database to our webpage using database connection.
$servername = “localhost”;
$username = “root”;
$password = “”;
$dbname = “MySQL”;
$conn = mysqli_connect($servername, $username, $password, $dbname);
?>
Now, we will write the code to show the comments.
$sql = SELECT * from comments LIMIT 2;
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) >0) {
while ($rows = mysqli_fetch_assoc($result))
{
echo “
”;
echo $row [‘author’]. “
”;
echo $row[‘message’]. “
;
}
} else {
echo “No comments”;
}
We need to write this php code inside an HTML form having a button with description Show more comments. The above code will only show first 2 comments. After adding below AJAX code, when we click on show more comments, then two more comments will be loaded without refreshing the page
Load more Comments
The load-comments.php file will have the PHP code we wrote above with a small variation. The LIMIT will be sent through the AJAX code instead of keeping it as LIMIT 2.
$comment_new_count = $POST [‘comment_new_count’];
$sql = SELECT * from comments LIMIT $comment_new_count;
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) >0) {
while ($rows = mysqli_fetch_assoc($result))
{
echo “
”;
echo $row [‘author’]. “
”;
echo $row[‘message’]. “
;
}
} else {
echo “No comments”;
}
The output of the above code will have 2 comments first, and it will keep on increasing with two more comments without refreshing the page as you click on Load more comments button.
Don't miss out!
Study Material
Quiz