Develop Reference

Javascript: The value of the property is null or undefined, not a Function object

Okay, Stumped. I just use code to show possibilities to customers (am self-employed).
Trying to show get-selected-text-from-IE11-Browser. Don't need cross-Browser and expert stuff just yet (if customer goes ahead).
Have tried to write a javascript function to get the selected text from the browser. This has worked fine when called direct (put function into Console via F12 facility) and this returns the selection. But when calling from Context Menu HTM script it fails with the mentioned error. The code to get the selected text comes from another context menu script that works fine when all the code is in the one HTM script (cmGoogleMapSelection_1.htm). I was just trying to be a little more efficient with reuse and learn a little more myself. I will return to in-line code if I can't resolve the issue (with help from your marvellous selves).
Keep getting the following error reported in the HTM script :
The value of the property 'myGetSelectedText' is null or undefined, not a Function object.
Have read a number of posts and tried to ensure that I have covered their suggestions. Still stumped, any help appreciated.
The code, first the 'function', then the 'script'; both script file and function file are in the same local file folder (please excuse the Debug code - gulp):
fn_myGetSelectedText.js:
function myGetSelectedText(pDefault) {
var zDbug = 1;
var zDbugMsg = "Debug: ";
var zSelection = "";
if (zDbug) {alert(zDbugMsg + "Starting Function 'myGetSelectedText' from fn_myGetSelectedText.js");}
zSelection = "" + window.getSelection().toString();
if (zDbug) {alert(zDbugMsg + " Selection= '" + zSelection + "'");}
if (zSelection == "") {
zSelection = pDefault;
alert(zDbugMsg + "Null selection, using: " + zDefault + " !");
}
return zSelection;
}//EndOf: Function -----
cmGoogleMapSelection_2.htm:
<!-- saved from url=(0016)http://localhost -->
<script type="text/javascript" src="fn_myGetSelectedText.js"></script>
<script type="text/javascript">
//- zDbug: 0 = false = no messages; 1 = true = show messages -----
var zDbug = 1;
var zDbugMsg = "Debug: ";
if (zDbug) {alert(zDbugMsg + "Starting cmGoogleMap_Selection2.htm V14");}
//- Google Maps stem URL & default location -----
var zMaps = "http://maps.google.co.uk/maps?hl=en&q=";
var zDefault = "+London";
var zSelection = myGetSelectedText(zDefault); //- Error occurs here <<<<<<<<<<<
if (zDbug) {alert(zDbugMsg + " Selection= '" + zSelection + "'");}
//- Build Maps URL -----
var zGo = zMaps + zSelection;
//- Open new Maps window -----
if (zDbug) {alert(zDbugMsg + "Issuing Window.Open on URL: " + zGo);}
window.open(zGo, "_blank");
//- Close this window -----
window.close()
</script>
<!-- Just to put something into the main code window so I know which one it is -->
<style>
p {font-family: "Lucida Console"; color: Red; font-size: 16pt;}
</style>
<p> >>-- Map Selected Text Function --<< <br>
>>-- . . 'myGetSelectedText' . . --<< </p>
I am hoping like heck that I haven't missed a bracket somewhere - embarrassing!
Other stuff: Windows 10 Pro (fully updated); 64 bit IE11; just javascript; Compatibility View OFF; Registry Keys/Values pointing where they should (cloned from working version).

While browser downloads fn_myGetSelectedText.js file from the internet, it does not stop parsing other code in your HTML. There's concurrent downloading of assets going on while browser parses the DOM.
when browser reaches this line var zSelection = myGetSelectedText(); it does not see myGetSelectedText defined on the window object at that moment thus throws out error.
What you want to do is wrap your script/code in your HTML into DOMContentLoaded event and call it once page load completes.
<script>
document.addEventListener("DOMContentLoaded", function(event) {
console.log("DOM fully loaded and parsed");
});
</script>
reference: https://developer.mozilla.org/en-US/docs/Web/Events/DOMContentLoaded

My guess would be that in your called function, pDefault is undefined, because you aren't passing a variable when you do the call.
So, this line: var zSelection = myGetSelectedText();
Should become: var zSelection = myGetSelectedText(zDefault);
HTH,
Jim

Why is HTML elements is displayed as text?

I'm working on a form builder website. After a form is built it must be saved in database. When the user clicks on a form name from the list of saved forms the form information is restored from database. One of the variables I will restore is the structure of the form. In javascript I wrote these lines of code:
var prefix_content='<!DOCTYPE HTML>\n<html lang="en-US">\n<head>\n<meta charset="UTF-8">\n<title> </title>\n </head>\n<body>\n ';
var sufex_content=' \n</body></html>';
var dynamic_content=String(text_content);
document.write(prefix_content + dynamic_content + sufex_content );
The variable dynamic_content contains the dynamic structure.
The problem is that prefix_content and sufex_content is displayed as html but dynamic_content is written in the page as text. Any one knows why is that or knows how to solve this problem.
Note: when I write the text in dynamic content statically between single quotes it is displayed as html not text.

If you're seeing the content retrieved from your database as plaintext, instead of HTML, its HTML entities are probably getting escaped somewhere along the way. Check the contents of your text_content variable (e.g. use console.log(text_content) and if you're seeing stuff like <div> instead of <div>, go on and find out where your escaping happens and either remove it or manually unescape.

TRY THIS:
var prefix_content='<!DOCTYPE HTML>\n<html lang="en-US">\n<head>\n<meta charset="UTF-8">\n<title> </title>\n </head>\n<body>\n ';
var sufex_content=' \n</body></html>';
var dynamic_content=String(text_content);
var parser = new DOMParser();
var el = parser.parseFromString(dynamic_content, "text/html");
document.write(prefix_content + el + sufex_content );
Or you can try this too: Using jQuery
var dynamic_content=String(text_content);
var el = $.parseHTML( dynamic_content );
document.write(prefix_content + el + sufex_content );

var content = "<div style='color:red;'>TEST</div>";
var prefix ='<!DOCTYPE HTML>\n<html lang="en-US">\n<head>\n<meta charset="UTF-8">\n<title>TEST</title>\n</head>\n<body>\n';
var suffix ='\n</body></html>';
var all = prefix + content + suffix;
var parser = new DOMParser();
var doc = parser.parseFromString(all, "text/html");
console.log(doc.children[0].outerHTML);
Instead of children[0] you can also go for:
doc.documentElement.outerHTML
Results in:
<html lang="en-US"><head>
<meta charset="UTF-8">
<title>TEST</title>
</head>
<body>
<div style="color:red;">TEST</div>
</body></html>

evaluate a post - loaded script

i have a String in html which should is post loaded in body.
var str = new String("<span>Hello</span><script>window.alert('hello');</script>");
document.getElementsByTagName('body')[0].innerHTML=str;
but the alert does not come. so i added this:
for(i=0;scr=document.getElementsByTagName('body')[0].getElementsByTagName('script')[i];i++) {
eval(src.innerHTML);
};
but even it doesn't work. can u solve my problem?

document.getElementsByTagName('body')[0].innerHTML="<span>Hello</span><script>window.alert('hello');<\/script>";
var alert_func = document.getElementsByTagName('script')[0].innerHTML
if(alert_func.indexOf("alert") != -1) {
eval(alert_func);
}
This code will first set the innerHTML of the <body> tags to <span>Hello</span><script>window.alert('hello');</script>. Then a variable alert_func will store the content between the <script> tags. If there is the word "alert" in alert_func, we will evaluate whatever is between the <script> tags and give the alert.

External Javascript File Fetch?

I am currently using this code:
var wordRandomizer = {
run: function (targetElem) {
var markup = this.createMarkup();
targetElem.appendChild(markup);
},
createMarkup: function () {
var that = this;
var frag = document.createDocumentFragment();
this.elem = document.createElement('span');
var button = document.createElement('button');
button.innerText = 'Change Item';
button.addEventListener('click', function () {
that.changeItem();
});
frag.appendChild(this.elem);
frag.appendChild(button);
return frag;
},
changeItem: function () {
var rand = this.getRandInt(1, this.items.length) - 1;
console.log(rand);
this.elem.innerText = this.items[rand];
},
getRandInt: function (min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min;
},
items: ['itemA', 'itemB', 'itemC', 'itemD']
};
wordRandomizer.run(document.body);
I code is a button which when pressed grabs one of the items in the list. However, I don't want the items to show on the same page as the generator as people simply look at the source code. How can I make it so once the button is pressed it grabs the random item from another location where people cannot view them all using the source code.
If it helps, you can see the code in action here - http://jsbin.com/ESOdELU/1/edit

I will give you a solution using PHP since it is a free scripting language and is the most likely to be supported by a host or default web server...
For starters, here is the code to include jquery and the basic AJAX script
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script type="text/JavaScript">
$(document).ready(function(){
$("#generate").click(function(){
$("#madlibs p").load("script.php");
});
});
</script>
Here is the code for script.php
<?php
header("Cache-Control: no-cache");
// For testing you can use an inline array like the lines below
// Just remove the comment slashes "//" from the beginning of the line
// and comment out the external declarations
//$actors = array('Denzel Washington','Michael J. Fox','Jim Carey','Boris Kodjoe');
//$roles = array('Mental Patient','Homeless Musician','Drag Queen Detective','Tormented Mathematician');
// In production, you would put these in a text file or a database.
// For $actors, put an entry on each line of a text file and save it as 'leads.txt'
// Do the same with a separate file for $roles (roles.txt).
$actors = file("leads.txt");
$roles = file("roles.txt");
// This selects a random element of each array on the fly
echo $prefixes[rand(0,count($actors)-1)] . " stars as a "
. $suffixes[rand(0,count($roles)-1)] . " in the next blockbuster film.";
// Example output:
// Michael J. Fox stars as a Tormented Mathematician in the next blockbuster film.
?>
Put this in the body of your page and be sure to style everything up for display.
<body>
<div id="madlibs"><p> </p></div>
<button id="generate">Surprise Me!</button>
</body>
A couple of notes:
- You can include your basic layout HTML in the script.php file and then would only need the ID of the DIV in which you will be displaying the result $("#madlibs")
You can use any server side language to achieve the same result, just swap out the external file call to the appropriate name and extension (.asp, .cfm, etc.)
Here is a link to the original tutorial that helped me with a similar project:
http://www.sitepoint.com/ajax-jquery/
I hope this helps. Sorry, but I couldn't come up with a purely Java of JavaScript solution on lunch.

Adding javascript variable to hyperlink within script

I have been trying to create a hyperlink using a variable defined earlier in the same function to append:
var NAMEVARIABLE = responseArray[i].Name;
var TITLE_Game = document.createElement("p");
TITLE_Game.className = "TITLE_Game";
TITLE_Game.innerHTML = "<a href='Game_NAMEVARIABLE.html'>Games</a>";
I have tried the following using the solution found here: Passing Javascript variable to <a href >
Games
But that didn't work. I then tried adding an ID:
<a id="link" href="Game_.html?propid=">Games</a>
And adding this to the script: document.links["link"].href += NAMEVARIABLE;
This didn't work either. These links are occuring within Isotope, which I've run into newbie-problems making sure my JSON data is loading before the script executes. That's all working now, but I'm not sure if the reason the above methods aren't working is because of a similar issue, or if they simply are not the proper way to go about this.
Any help is much appreciated. Thank you

first of all, try debug your variable :
var NAMEVARIABLE = responseArray[i].Name;
alert(NAMEVARIABLE);
is it returning the desired return value or not.
and then the second thing, in your first style of script, try this instead :
TITLE_Game.innerHTML = "<a href='Game_"+NAMEVARIABLE+".html'>Games</a>";
I assumed you have (static) html collection with game_[number_id].html format
and if it's so, you can try further with your second style of script, and change it to this :
Games
you need to learn further about javascript strings concatenation

Use string concatenation to build up your inner html string.
Example:
var nameVariable = 'Foo';
var innerHtmlText = nameVariable + 'bar';
$('#someElement').html(innerHtmlText);
The contents of someElement will then contain the text: 'Foobar';

You just need string concatenation. modify link's href onclick would be considered as spam in most modern browser.
<div id="result">
the result:
</div>
<script type="text/javascript">
var name = "foo_bar";
var url = "page.html?key=" + name; //or.. "page_" + name + ".html";
var link = 'link here';
$("#result").addClass("g_title");
$("#result").append(link);
</script>

This can be achieved by either (i.e. pure JS or jQuery) ways without much hassle. Suppose you have this <a> element with some href
<a id="Link" href="/collection/categories/">Games</a>
Pure JavaScript way:
window.onload = function() {
var link= document.getElementById('Link'),
url = link.href + responseArray[i].Name + '.html';
link.setAttribute('href', url);
}
Using Jquery:
$(function(){
var link= $('#Link'),
url = link.attr('href') + responseArray[i].Name + '.html';
link.attr('href', url);
});