Wordpress, admin menu, Ajax 400 bad request - ajax

Question

I am trying to delete database row using button, (this is inside my plugin in admin area)
but i am not able to figure out why my ajax call is not working.
Every time i try i recive: 400 bad request all the time.
So i did not manage it yet to call the function properly
this is my button:
<button class="deletebutton" <?php echo 'value="' . $data->id . '"' ?> class="delete"> delete</button>
And i use:
add_action('wp_ajax_delete_data', 'delete_data');
MY function: (i know it work i have use it many times before
'function delete_data($element_id){
global $wpdb;
$tablename = $wpdb->prefix . 'my_table';
$wpdb->delete($tablename, array('id' => $element_id));
}'
And Jquery/AJAX <- here is the problem i think
<script>
var ajaxurl = '<?php echo admin_url('admin-ajax.php'); ?>';
jQuery(document).ready(function() {
jQuery(".deletebutton").click(function(){
var element_id = this.value;
jQuery.ajax({
url: ajaxurl,
type: 'POST',
action: 'delete_data',
data: element_id
dataType: 'data',
});
});
});
</script>

Answer 1

You have given the wrong actions name. see more information here
Change this line
`add_action('wp_ajax_worktmp_delete_absence', 'delete_data');`
With this
`add_action('wp_ajax_delete_data', 'delete_data');`

Answer 2

So the proper of doing this is
Create a separate js file or you can use it upon the existing js file like following while you are enqueuing your script:
wp_register_script( $this->plugin_name, plugin_dir_url( __FILE__ ) . '{your_js_file_location}', array( 'jquery' ), $this->version, false );
wp_localize_script( $this->plugin_name, 'test_ajax_object', array( 'ajaxurl' => admin_url( 'admin-ajax.php' ) ) );
wp_enqueue_script($this->plugin_name);
Then
add_action('wp_ajax_delete_data', 'delete_data');
if it is for normal user hten add the folowwing as well
add_action('wp_ajax_nopriv_delete_data', 'delete_data');
Then in your js file
jQuery(document).ready(function($) {
$(".deletebutton").click(function(){
var element_id = this.value;
$.ajax({
url: test_ajax_object.ajaxurl,
type : 'post',
data : {
"action" : 'delete_data', "data_id":element_id},
success: function( response ) {
console.log(response);
}
});
});
});
And in your php file
function delete_data(){
global $wpdb;
$element_id = $_POST['data_id'];
$tablename = $wpdb->prefix . 'my_table';
$wpdb->delete($tablename, array('id' => $element_id));
}
This might work, try once