Develop Reference

Calling PHP via a HTML anchor on the same page

I am currently reading through a piece of code provided by my faculty and I am having troubles understanding how it works.
Specifically how the anchor is linked to the php without method="post" or method="get".
Kindly appreciate if anyone could explain or link me to relevant materials to do further readings. Much thanks.
if (!isset($_SESSION['cart'])){
$_SESSION['cart'] = array();
}
if (isset($_GET['buy'])) {
$_SESSION['cart'][] = $_GET['buy'];
header('location: ' . $_SERVER['PHP_SELF']. '?' . SID);
exit();
}
for ($i=0; $i<count($items); $i++){
echo "<tr>";
echo "<td>" .$items[$i]. "</td>";
echo "<td>$" .number_format($prices[$i], 2). "</td>";
echo "<td><a href='" .$_SERVER['PHP_SELF']. '?buy=' .$i. "'>Buy</a></td>";
echo "</tr>";
}

Cart for bought items indexes is created in session if it's not there yet.
if (!isset($_SESSION['cart'])){
$_SESSION['cart'] = array();
}
When link with buy query parameter is opened, buy value is added to session cart. After that page is redirected to location without buy parameter.
if (isset($_GET['buy'])) {
$_SESSION['cart'][] = $_GET['buy'];
header('location: ' . $_SERVER['PHP_SELF']. '?' . SID);
exit();
}
List of items to buy is printed on page (i quess code in question is not full).
for ($i=0; $i<count($items); $i++){
echo "<tr>";
echo "<td>" .$items[$i]. "</td>";
echo "<td>$" .number_format($prices[$i], 2). "</td>";
echo "<td><a href='" .$_SERVER['PHP_SELF']. '?buy=' .$i. "'>Buy</a></td>";
echo "</tr>";
}
Links open pages with GET method.
Link query parameters can be accessed by special $_GET variable

Execute AJAX from Main file after previously inserting data through AJAX

I have a questions for which I need some help.
I have a page which, after it is finished loading, executes an AJAX, creates a table in PHP containing 2 buttons: 1 change password, the other is delete. Once the table is complete it is injected into a div in the main file. That works great so far. Now after that table is loaded, I want to be able to call another AJAX function linked in the JS file in the main page. So I have 3 components:
1. <div id="DbInfo"></div>
That is where I add the information from the users.
my php which executes the code and gets the information from my database.
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$sql = "SELECT LoginName FROM table";
$res = mysqli_query($conn, $sql);
if (mysqli_num_rows($res) > 0) {echo "<center>";
echo "<table border='1'>";
echo "<tr>";
echo "<td>User</td>";
echo "<td colspan=2 align=center>Available Functions</td>";
echo "</tr>";
while($row = mysqli_fetch_assoc($res)) {
echo "<tr>";
echo "<td>" . $row['User'] . "</td>";
echo "<td><button type='button' class='smallbutton' id='removeUser' value='" . $row['LoginName'] . "'>Delete User</button></td>";
echo "<td><button type='button' class='smallbutton' id='CPW' value='" . $row['LoginName'] . "'>Change Password</button></td>";
echo "</tr>";
}
echo "</table>";
echo "</center>";
} else {
echo "";
}
mysqli_close($conn);
And lastly the AJAX which does the injection of the created table into the HTML:
$(document).ready(function(){
$.ajax({
method: "POST",
url: "UserData.php",
success: function(data){
//document.getElementById("DbInfo").innerHTML = data;
document.getElementById("DbInfo").html(data);
}
});
});
Again, these functions are working fine. What I want to do after the page is done, be able to click one of these injected buttons and execute another AJAX. Unfortunately the standard declaration that I use for AJAX does not work.
$(document).ready(function(){
$("#removeUser").click(function(){
The question: How can I make sure after the table is injected, that I can call an AJAX function which is linked as an external source (<script src="script.js"></script>) in the main document?
Thanks for your help.

try :
$('#DbInfo').on('click', 'button[id="removeUser"]', function(i,e){
console.log('remove :' + $(this).val());
});

Add onclick event to a dynamic created link (PHP)

I have many links which are dynamically created with PHP and now I want to add an onclick event.
while($row = mysqli_fetch_array($xyz)) {
echo "<tr>";
echo "<td><a href=\"test.php?parameter=". $row['z'] ."\" target=\_blank>" . $row['z'] . "</a></td>";
echo "</tr>";}
but I want like this:
while($row = mysqli_fetch_array($xyz) {
echo "<tr>";
echo "<td><a href=\"test.php?parameter=". $row['z'] ."\" target=\_blank>" . $row['z'] . onclick="test()"</a></td>";
echo "</tr>";}
is this possible?

I am not sure if I understood what exactly you are asking but I try to answer you the same:
You can't record a normal JS variable in a page session and then to access to it after the loading of a page.
For this case you can use cookies (that are accessible via server-side too):
// put this code into methods that users suggested you.
document.cookie = "value_selected=something"
and once page is loaded:
var cookies = document.cookie.split(';');
var value_selected = JSON.parse(JSON.stringify(cookies[YOUR_COOKIE].split("=")[0]))
or server side:
echo "<td><a href=\"test.php?parameter=". $row['z'] ."\" data-something=htmlentities($_COOKIE['value_selected']) target=\_blank>" . $row['z'] . "</a></td>"; //(example)
Or more simply, pass the value selected through query
?value_selected=something //elaborate the new link in the method users suggested you
and
in server-side, use $['GET'] to obtain all values in query string.
IMHO I think the first choice is simpler than second.
I hope I helped you

Try Like this
while($row = mysqli_fetch_array($xyz) {
echo "<tr>";
echo "<td><a class='myclick' href=\"test.php?parameter=". $row['z'] ."\" target=\_blank>" . $row['z'] . **onclick="test()"**</a></td>";
echo "</tr>";}
i have added a class to link as myclick
and in jquery
$(document).on('click','.myclick',function(e){
e.preventDefault();
alert('clicked');
});

You can try like this..just a simple way.
<script type="text/javascript">
function test(){
alert('test');
}
</script>
<?php
while($row = mysqli_fetch_array($xyz) {
echo "<tr>";
echo "<td><a href='your link' onclick='test()'></a></td>";
echo "</tr>";
}
?>

Getting text and sending it to a php function using javascript

I have a php function which displays all the data in my mysql table and allows the user to delete data not needed. I managed to get the data to show in a table, get the delete button to ask for confirmation using javascript, but when i try to get the value in the 2nd cell of the table with the query result (the name) and display it on the confirmation tab, it says undefined. Why is that happening? From what i understand, document.getElementById("myText").value where myText is the id of the cell, should return the value in the cell, correct? Also, how would i call and send that value to another php file that has the delete query?
<?php
$row = mysqli_fetch_array($result);
echo "<table>";
echo "<tr class='header'><td class='header'>Delete</td>";
echo "<td class='header'>Added</td>";
echo "<td class='header'>Name</td>";
echo "<td class='header'>Genre</td>";
echo "<td class='header'>Developer</td>";
echo "<td class='header'>Rating</td></tr>";
?>
<script type="text/javascript">
function ConfirmDelete(){
var name = document.getElementById("name").value;
if (confirm("Delete" +name+"?")){
//send the value and call the php
}
}
</script>
<?php
for ($x=0; $row; $x++) {
echo "<tr><td><input type='button' onclick='ConfirmDelete()' name='deleteGame' value='DELETE'></td><td>$row[Added]</td><td id='name'>$row[Name]</td><td>$row[Genre]</td><td>$row[Developer]</td><td align='right'>$row[Rating]</td></tr>";
$row = mysqli_fetch_array($result);
}
?>
</table>

PHP and Javascript : Multiple Buttons inside a table

I'm working with PHP, Javascript and MySQL. My goal is to have a button on each row. The button should call the onclick fucntion and href to another page.
My problem with my code -- > only the button from the first row is clickable...
I'm assuming the Button ID needs to be unique for each button.. What are my options to make all buttons clickable ?
// printing table rows
while($row = mysqli_fetch_row($result))
{
echo "<tr>";
echo "<td><button id='greenbutton' class='small pill green'>$row[0]</button></td>";
echo "<td><img src='/iframe/$row[7]'>&nbsp$row[5]</td>";
echo "<td>$row[4]&nbspmin(s)</td>";
echo "<td><img src='/iframe/$row[6]'>&nbsp$row[2]</td>";
if ($row[3] == 0) {
echo "<td>Unknown</td>";
}
else {echo "<td>$row[3]</td>";}
echo "</tr>\n";
// FOR ONCLICK
echo "<script type='text/javascript'>";
echo "document.getElementById('greenbutton').onclick = function () {";
echo "location.href = '/user';";
echo "};";
echo "</script>";
}
echo "</table></center>";

You're id's of your dom elements should be unique at all time. To achieve this you can add a counter in your while so that all of your button have an id like 'greenbutton1', 'greenbutton2', 'greenbutton3', etc.
$cnt = 1;
// printing table rows
while($row = mysqli_fetch_row($result))
{
echo "<tr>";
echo "<td><button id='greenbutton$cnt' class='small pill green'>$row[0]</button></td>";
echo "<td><img src='/iframe/$row[7]'>&nbsp$row[5]</td>";
echo "<td>$row[4]&nbspmin(s)</td>";
echo "<td><img src='/iframe/$row[6]'>&nbsp$row[2]</td>";
if ($row[3] == 0) {
echo "<td>Unknown</td>";
}
else {echo "<td>$row[3]</td>";}
echo "</tr>\n";
$cnt++;
}
echo "</table></center>";
In that exemple I didnt add your javascript function into your while loop because it look like the same function for all your buttons. I suggest you add the function only once but bound it with the class selector instead of the id selector like this.
// FOR ONCLICK
echo "<script type='text/javascript'>";
echo "document.getElementsByClassName('myGreenButtons').onclick = function () {";
echo "location.href = '/user';";
echo "};";
echo "</script>";
And then add the myGreenButtons class to your buttons in the while loop. You can also use attributes or types selector to gather your dom elements in a more flexible way. Check out theses links for more info:
http://www.w3schools.com/cssref/css_selectors.asp
http://www.htmlgoodies.com/beyond/javascript/using-javascripts-css3-selectors.html#fbid=FhIuAA6GqpH
hope this helps!

echo "<td><a href='/user'><button class='small pill green'>$row[0]</button></a></td>";
...will do the trick.