Error onclick Uncaught ReferenceError

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Error onclick Uncaught ReferenceError

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#1 by (2 votes)
#2 by (2 votes)

1

I want to call a method of my JS and pass a variable but it gives me Uncaught ReferenceError, how can I fix this.

PHP / HTML

<div class="col-4 col-md-2 topbutton ">                                        
                            <input  name="cart_id" value=" <?php echo$q["product_id"]; ?>"> 
                            <input type="button" class="btn btn-danger eliminar_cart" value="Elimina" id="<?php echo$q["product_id"]; ?>" onclick="eliminar_cart(this)">                                           
                        </div>

js

function eliminar_cart(id) {
    var cart_id = id.id;
    alert(cart_id);}

javascript html5 php

asked by Aaron M Fonseca 26.09.2018 в 02:55

source

2 answers

2

There are two recommended practices you are forgetting:

The JS code must always be inside a DOMContentLoaded block, so never try to use DOM elements before the DOM is fully loaded.

It is convenient that our HTML code is as independent as possible. Therefore, avoid putting functions inside the HTML elements. In the example I removed the function that was inside the button, changing it by a listener in JS. This will also give us the advantage of this directly.

I leave the code, as a possibility to solve the problem by applying good practices.

<script>
  document.addEventListener("DOMContentLoaded", function(event) {
    var btn1 = document.getElementById("btn1");
    btn1.addEventListener("click", function(e) {
        alert(this.id);
    }, false);
  });
</script>

<div class="col-4 col-md-2 topbutton ">
  <input name="cart_id" value="Test...">
  <input type="button" class="btn btn-danger eliminar_cart" value="Elimina" id="btn1">
</div>

answered by 26.09.2018 в 03:36

What is stdcall and what is it used for? Send a variable from PHP to HTML?

score 2 · Accepted Answer

Depending on the value that is returned in $q , it is only necessary to place your js code at the beginning of your html file (at the beginning of body or in head ), this between tags <script> or including the js file.

function eliminar_cart(id) {
    var cart_id = id.id;
    alert("msg:" + cart_id);}

<div class="col-4 col-md-2 topbutton ">          <input  name="cart_id" value="valorRetornadoen$q"> 
 <input type="button" class="btn btn-danger eliminar_cart" value="Elimina" id="idRetornadoen$q" onclick="eliminar_cart(this);">                                           
                        </div>