Vue Is Not Defined

Question

I am trying to build a demo app with Vue.js. What I am getting is an odd error that Vue is not defined.

Solution 1:

You missed the order, first goes:

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/1.0.18/vue.min.js"></script>

and then:

<script>
    var demo = new Vue({
        el: '#demo',
        data: {
            message: 'Hello Vue.js!'
        }
    });
</script>

And type="JavaScript" should be type="text/javascript" (or rather nothing at all)

Solution 2:

Sometimes the problem may be if you import that like this:

const Vue = window.vue;

this may overwrite the original Vue reference.

Solution 3:

try to fix type="JavaScript" to type="text/javascript" in you vue.js srcipt tag, or just remove it. Modern browsers will take script tag as javascript as default.

Solution 4:

I got this error but as undefined due to the way I included js files

Baca Juga

Initailly i had

<script src="~/vue/blade-account-update-credit-card-vue.js" asp-append-version="true"></script>
<script src="~/lib/vue/vue_v2.5.16.js"></script>

in the end of my .cshtml page GOT Error Vue not Defined but later I changed it to

<script src="~/lib/vue/vue_v2.5.16.js"></script> 
<script src="~/vue/blade-account-update-credit-card-vue.js" asp-append-version="true"></script>

and magically it worked. So i assume that vue js needs to be loaded on top of the .vue

Solution 5:

I found two main problems with that implementation. First, when you import the vue.js script you use type="JavaScript" as content-type which is wrong. You should remove this type parameter because by default script tags have text/javascript as default content-type. Or, just replace the type parameter with the correct content-type which is type="text/javascript".

The second problem is that your script is embedded in the same HTML file means that it may be triggered first and probably the vue.js file was not loaded yet. You can fix this using a jQuery snippet $(function(){ /* ... */ }); or adding a javascript function as shown in this example:

// Verifies if the document is ready
function ready(f) {
  /in/.test(document.readyState) ? setTimeout('ready(' + f + ')', 9) : f();
}

ready(function() {
  var demo = new Vue({
    el: '#demo',
    data: {
      message: 'Hello Vue.js!'
    }
  })
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="demo">
  <p>{{message}}</p>
  <input v-model="message">
</div>

JavaScript Sample