ECMAScript
ECMAScript

Reputation: 4649

Uncaught ReferenceError: function is not defined with onclick

I'm trying to make a userscript for a website to add custom emotes. However, I've been getting a lot of errors.

Here is the function:

function saveEmotes() {
    removeLineBreaks();
    EmoteNameLines = EmoteName.value.split("\n");
    EmoteURLLines = EmoteURL.value.split("\n");
    EmoteUsageLines = EmoteUsage.value.split("\n");

    if (EmoteNameLines.length == EmoteURLLines.length && EmoteURLLines.length == EmoteUsageLines.length) {
        for (i = 0; i < EmoteURLLines.length; i++) {
            if (checkIMG(EmoteURLLines[i])) {
                localStorage.setItem("nameEmotes", JSON.stringify(EmoteNameLines));
                localStorage.setItem("urlEmotes", JSON.stringify(EmoteURLLines));
                localStorage.setItem("usageEmotes", JSON.stringify(EmoteUsageLines));
                if (i == 0) {
                    console.log(resetSlot());
                }
                emoteTab[2].innerHTML += '<span style="cursor:pointer;" onclick="appendEmote(\'' + EmoteUsageLines[i] + '\')"><img src="' + EmoteURLLines[i] + '" /></span>';
            } else {
                alert("The maximum emote(" + EmoteNameLines[i] + ") size is (36x36)");
            }
        }
    } else {
        alert("You have an unbalanced amount of emote parameters.");
    }
}

The span tag's onclick calls this function:

function appendEmote(em) {
    shoutdata.value += em;
}

Every time I click a button that has an onclick attribute, I get this error:

Uncaught ReferenceError: function is not defined.

Update

I tried using:

emoteTab[2].innerHTML += '<span style="cursor:pointer;" id="'+ EmoteNameLines[i] +'"><img src="' + EmoteURLLines[i] + '" /></span>';
document.getElementById(EmoteNameLines[i]).addEventListener("click", appendEmote(EmoteUsageLines[i]), false);

But I got an undefined error.

Here is the script.

I tried doing this to test if listeners work and they don't for me:

emoteTab[2].innerHTML = '<td class="trow1" width="12%" align="center"><a id="togglemenu" style="cursor: pointer;">Custom Icons</a></br><a style="cursor: pointer;" id="smilies" onclick=\'window.open("misc.php?action=smilies&amp;popup=true&amp;editor=clickableEditor","Smilies","scrollbars=yes, menubar=no,width=460,height=360,toolbar=no");\' original-title="">Smilies</a><br><a style="cursor: pointer;" onclick=\'window.open("shoutbox.php","Shoutbox","scrollbars=yes, menubar=no,width=825,height=449,toolbar=no");\' original-title="">Popup</a></td></br>';
document.getElementById("togglemenu").addEventListener("click", changedisplay,false);

Upvotes: 135

Views: 619792

Answers (8)

Marius Okouin
Marius Okouin

Reputation: 7

for me I've just put the function out of pageReady scope and it works jQuery(document).ready(function(){ don't the function here }

put your function here with script tag

Upvotes: 0

bendecko
bendecko

Reputation: 2783

Check the casing of your functions.

onclick="sillyLongFunctionName" 

and

function sillylongFunctionName() { ...

Are not identical. Hard to spot sometimes!

Upvotes: 0

Anna
Anna

Reputation: 47

See that your function is not in a callback function if you are using an external js file. Removing the callback function would do the trick

(function() {  //comment this out

//your code

})(); //comment this out

Upvotes: -2

Alferd Nobel
Alferd Nobel

Reputation: 3949

I got this resolved in angular with (click) = "someFuncionName()" in the .html file for the specific component.

Upvotes: 6

Mouhcine Mtg
Mouhcine Mtg

Reputation: 79

I think you put the function in the $(document).ready....... The functions are always provided out the $(document).ready.......

Upvotes: 7

Make sure you are using Javascript module or not?! if using js6 modules your html events attributes won't work. in that case you must bring your function from global scope to module scope. Just add this to your javascript file: window.functionName= functionName;

example:

<h1 onClick="functionName">some thing</h1>

Upvotes: 30

Vũ Đức Vĩ
Vũ Đức Vĩ

Reputation: 29

If the function is not defined when using that function in html, such as onclick = ‘function () ', it means function is in a callback, in my case is 'DOMContentLoaded'.

Upvotes: -2

Brock Adams
Brock Adams

Reputation: 93473

Never use .onclick(), or similar attributes from a userscript! (It's also poor practice in a regular web page).

The reason is that userscripts operate in a sandbox ("isolated world"), and onclick operates in the target-page scope and cannot see any functions your script creates.

Always use addEventListener()Doc (or an equivalent library function, like jQuery .on()).

So instead of code like:

something.outerHTML += '<input onclick="resetEmotes()" id="btnsave" ...>'


You would use:

something.outerHTML += '<input id="btnsave" ...>'

document.getElementById ("btnsave").addEventListener ("click", resetEmotes, false);

For the loop, you can't pass data to an event listener like that See the doc. Plus every time you change innerHTML like that, you destroy the previous event listeners!

Without refactoring your code much, you can pass data with data attributes. So use code like this:

for (i = 0; i < EmoteURLLines.length; i++) {
    if (checkIMG (EmoteURLLines[i])) {
        localStorage.setItem ("nameEmotes", JSON.stringify (EmoteNameLines));
        localStorage.setItem ("urlEmotes", JSON.stringify (EmoteURLLines));
        localStorage.setItem ("usageEmotes", JSON.stringify (EmoteUsageLines));
        if (i == 0) {
            console.log (resetSlot ());
        }
        emoteTab[2].innerHTML  += '<span style="cursor:pointer;" id="' 
                                + EmoteNameLines[i] 
                                + '" data-usage="' + EmoteUsageLines[i] + '">'
                                + '<img src="' + EmoteURLLines[i] + '" /></span>'
                                ;
    } else {
        alert ("The maximum emote (" + EmoteNameLines[i] + ") size is (36x36)");
    }
}
//-- Only add events when innerHTML overwrites are done.
var targetSpans = emoteTab[2].querySelectorAll ("span[data-usage]");
for (var J in targetSpans) {
    targetSpans[J].addEventListener ("click", appendEmote, false);
}

Where appendEmote is like:

function appendEmote (zEvent) {
    //-- this and the parameter are special in event handlers.  see the linked doc.
    var emoteUsage  = this.getAttribute ("data-usage");
    shoutdata.value += emoteUsage;
}


WARNINGS:

  • Your code reuses the same id for several elements. Don't do this, it's invalid. A given ID should occur only once per page.
  • Every time you use .outerHTML or .innerHTML, you trash any event handlers on the affected nodes. If you use this method beware of that fact.

Upvotes: 188

Related Questions