I started to work with Angular for a work-related project and am following this tutorial https://www.youtube.com/watch?v=2OHbjep_WjQ&t=1874s (minute 50:30)
Which led me to following code-snippet
i=0;
doSomeHeavyTask()
{
console.log('Called ${this.i++} times');
}
The browser should print following message into the console:
Called 0 times
Called 1 times
...
But VSCode doesnt recognize
${this.i++}
as an JS-expression, therefore it prints just the plain text.
The syntax also doesn't get highlighted and is handled like a normal string.
I can't find the reason behind this behaviour and couldn't find any other person with that problem. I would be happy if somebody could come up with a suggestion or a solution :)
You used the wrong character for the template literal syntax. It should be the backtick (on keyboard, usually left of the 1 key), not the single quotation mark.
console.log(`Called ${this.i++} times`);
Using Visual Studio 2012, on a Razor view page, in the JavaScript section, I am getting what I think is a battle between Razor syntax vs JavaScript syntax. In particular, the trailing semicolon in the script section is flagged by intellisense and a compiler warning (not error) is delivered:
'Warning 13 Syntax error'.
If I remove it, then I get a statement termination recommendation (ReSharper in this case, but just good practice).
<script type="text/javascript">
$().ready(function(){
var customer = #Html.Raw(ViewBag.CustomerJSON); // <- Razor (I think) doesn't like this semicolon
});
</script>
Is this a bug in Razor? If so, is there a way I can rewrite this to avoid this issue?
Is this a bug in Razor?
Absolutely not. Run your application, and it will work as expected.
It is a bug in the tools you are using (Visual Studio 2012, ReSharper, ...) that are incapable of recognizing perfectly valid syntax and warning you about something that you shouldn't be warned about. You could try opening an issue on the Microsoft Connect site and signalling this bug if that hasn't already been done.
Since this still seems to be happening and it is a nuisance I figured I will at least let others know what I ended up using as a "hack". I don't want to ignore the warning and would rather accept a hokier syntax (and yes someone is going to say this will kill performance :))
What I use as a workaround is to use a client side addition at the end. For me this error occurred on defining an "integer" constant, so
window.foo = #(Model.Something);
gave me the good old semicolon error. I simply changed this to:
window.foo = #Model.Something + 0;
(In the stated questions case you should just be able to add '', so + ''.
I know there is a whole another addition happening on the client and it isn't elegant, but it does avoid the error. So use it or don't, but I prefer this over seeing the warning/error.
If someone knows of a server-side syntactical workaround for this I would prefer this to the client-side one, so please add.
I found that wrapping the Razor syntax in a JavaScript identity function also makes the IDE happy.
<script type="text/javascript">
#* I stands for Identity *#
function I(obj) { return obj; }
$().ready(function(){
var customer = I(#Html.Raw(ViewBag.CustomerJSON));
});
</script>
This worked for me:
var customer = #Html.Raw(ViewBag.CustomerJSON + ";")
Here's a workaround for booleans:
var myBool = #(Model.MyBool ? "true;" : "false;")
This worked for me
#Html.Raw(string.Format("var customer = {0};", ViewBag.CustomerJSON));
<script type="text/javascript">
$().ready(function(){
var customerName = ('#ViewBag.CustomerName'); // <- wrap in parens
});
</script>
Isn't it as simple as wrapping in parentheses? Putting values through the console seem to work fine with no side effect.
It works for strings, but it still gives the error for non-quoted values, but I still like this for string values. For numbers you could just use parseInt('#Model.TotalResultCount', 10).
This is probably the beginning of many questions to come.
I have finished building my site and I was using Firefox to view and test the site. I am now IE fixing and am stuck at the first JavaScript error which only IE seems to be throwing a hissy about.
I run the IE 8 JavaScript debugger and get this:
Object doesn't support this property or method app.js, line 1 character 1
Source of app.js (first 5 lines):
var menu = {};
menu.current = "";
menu.first = true;
menu.titleBase = "";
menu.init = function(){...
I have tested the site in a Webkit browser and it works fine in that.
What can I do to fix this? The site is pretty jQuery intensive so i have given up any hope for getting it to work in IE6 but I would appreciate it working in all the others.
UPDATE: I have upload the latest version of my site to http://www.frankychanyau.com
In IE8, your code is causing jQuery to fail on this line
$("title").text(title);
in the menu.updateTitle() function. Doing a bit of research (i.e. searching with Google), it seems that you might have to use document.title with IE.
Your issue is (probably) here:
menu.updateTitle = function(hash){
var title = menu.titleBase + ": " + $(hash).data("title");
$("title").text(title); // IE fails on setting title property
};
I can't be bothered to track down why jQuery's text() method fails here, but it does. In any case, it's much simpler to not use it. There is a title property of the document object that is the content of the document's title element. It isn't marked readonly, so to set its value you can simply assign a new one:
document.title = title;
and IE is happy with that.
It is a good idea to directly access DOM properties wherever possible and not use jQuery's equivalent methods. Property access is less troublesome and (very much) faster, usually with less code.
Well, your line 1 certainly looks straight forward enough. Assuming the error line and number is not erroneous, it makes me think there is a hidden character in the first spot of your js file that is throwing IE for a fit. Try opening the file in another text editor that may support display of normally hidden characters. Sometimes copying/pasting the source into a super-basic text-editor, like Notepad, can sometimes strip out non-displayable characters and then save it back into place directly from Notepad.
I'm running IE8 in normal mode (whatever it is when compatibility is NOT turned on) on WinXP. I'm doing maintenance on a rails app that was written a few years ago. Often when I load a page, and/or refresh a page, it reports different javascript errors. When I look at the errors in the Developer tool, it appears that a javascript file hasn't loaded completely. So the errors are frequently syntax related, such as '}' expected.
Trailing comma in object literal or array declaration? Some browsers accept this without error, IE does not.
// Trailing commas are bad
var someArray = [
"thing",
"last",
];
var someObject = {
one: "thing",
after: "another",
};
As galambalazs suggested in his comment, jslint will pick up problems like this for you.
Cntrl + F your javascript file and look for a rogue "return" statement.
I ran into this problem on older versions of IE. It was never reproducible in a test harness and left no trace in server logs, but consistently affected a very small percentage of IE 6 loads.
The solution was to have the embedding HTML file double check that the JS was loaded.
foo.js:
// do all the real work.
// As the last statement, set a variable indicating completion.
foo_js_fully_loaded = true;
foo.html:
<script src=foo.js></script>
<script>if (!foo_js_fully_loaded) { /* reload the page */ }</script>
Some users are reporting occasional JS errors on my site. The error message says "Expected identifier, string or number" and the line number is 423725915, which is just an arbitrary number and changes for each report when this occurs.
This mostly happens with IE7/ Mozilla 4.0 browsers.
I scanned my code a bunch of times and ran jslint but it didn't pick anything up - anyone know of the general type of JS problems that lead to this error message?
The cause of this type of error can often be a misplaced comma in an object or array definition:
var obj = {
id: 23,
name: "test", <--
}
If it appears at a random line, maybe it's part of an object defintion you are creating dynamically.
Using the word class as a key in a Javascript dictionary can also trigger the dreaded "Expected identifier, string or number" error because class is a reserved keyword in Internet Explorer.
BAD
{ class : 'overlay'} // ERROR: Expected identifier, string or number
GOOD
{'class': 'overlay'}
When using a reserved keyword as a key in a Javascript dictionary, enclose the key in quotes.
Hope this hint saves you a day of debugging hell.
Actually I got something like that on IE recently and it was related to JavaScript syntax "errors". I say error in quotes because it was fine everywhere but on IE. This was under IE6. The problem was related to JSON object creation and an extra comma, such as
{ one:1, two:2, three:3, }
IE6 really doesn't like that comma after 3. You might look for something like that, touchy little syntax formality issues.
Yeah, I thought the multi-million line number in my 25 line JavaScript was interesting too.
Good luck.
This is a definitive un-answer: eliminating a tempting-but-wrong answer to help others navigate toward correct answers.
It might seem like debugging would highlight the problem. However, the only browser the problem occurs in is IE, and in IE you can only debug code that was part of the original document. For dynamically added code, the debugger just shows the body element as the current instruction, and IE claims the error happened on a huge line number.
Here's a sample web page that will demonstrate this problem in IE:
<html>
<head>
<title>javascript debug test</title>
</head>
<body onload="attachScript();">
<script type="text/javascript">
function attachScript() {
var s = document.createElement("script");
s.setAttribute("type", "text/javascript");
document.body.appendChild(s);
s.text = "var a = document.getElementById('nonexistent'); alert(a.tagName);"
}
</script>
</body>
This yielded for me the following error:
Line: 54654408
Error: Object required
Just saw the bug in one of my applications, as a catch-all, remember to enclose the name of all javascript properties that are the same as keyword.
Found this bug after attending to a bug where an object such as:
var x = { class: 'myClass', function: 'myFunction'};
generated the error (class and function are keywords)
this was fixed by adding quotes
var x = { 'class': 'myClass', 'function': 'myFunction'};
I hope to save you some time
http://closure-compiler.appspot.com/home will pick this error up with an accurate reference to the actual line number in the offending script.
As noted previously, having an extra comma threw an error.
Also in IE 7.0, not having a semicolon at the end of a line caused an error. It works fine in Safari and Chrome (with no errors in console).
IE7 is much less forgiving than newer browsers, especially Chrome. I like to use JSLint to find these bugs. It will find these improperly placed commas, among other things. You will probably want to activate the option to ignore improper whitespace.
In addition to improperly placed commas, at this blog in the comments someone reported:
I've been hunting down an error that only said "Expected identifier"
only in IE (7). My research led me to this page. After some
frustration, it turned out that the problem that I used a reserved
word as a function name ("switch"). THe error wasn't clear and it
pointed to the wrong line number.
Remove the unwanted , sign in the function. you will get the solution.
Refer this
http://blog.favrik.com/2007/11/29/ie7-error-expected-identifier-string-or-number/
This error occurs when we add or missed to remove a comma at the end of array or in function code. It is necessary to observe the entire code of a web page for such error.
I got it in a Facebook app code while I was coding for a Facebook API.
<div id='fb-root'>
<script type='text/javascript' src='http://connect.facebook.net/en_US/all.js'</script>
<script type='text/javascript'>
window.fbAsyncInit = function() {
FB.init({appId:'".$appid."', status: true, cookie: true, xfbml: true});
FB.Canvas.setSize({ width: 800 , height: 860 , });
// ^ extra comma here
};
</script>
This sounds to me like a script that was pulled in with src, and loaded just halfway, causing a syntax error sine the remainder is not loaded.
IE7 has problems with arrays of objects
columns: [
{
field: "id",
header: "ID"
},
{
field: "name",
header: "Name" , /* this comma was the problem*/
},
...
Another variation of this bug: I had a function named 'continue' and since it's a reserved word it threw this error. I had to rename my function 'continueClick'
Maybe you've got an object having a method 'constructor' and try to invoke that one.
You may hit this problem while using Knockout JS. If you try setting class attribute like the example below it will fail:
<span data-bind="attr: { class: something() }"></span>
Escape the class string like this:
<span data-bind="attr: { 'class': something() }"></span>
My 2 cents.
I too had come across this issue. I found below two solutions.
1). Same as mentioned by others above, remove extra comma from JSON object.
2). Also, My JSP/HTML was having . Because of this it was triggering browser's old mode which was giving JS error for extra comma. When used it triggers browser's HTML5 mode(If supported) and it works fine even with Extra Comma just like any other browsers FF, Chrome etc.
Here is a easy technique to debug the problem:
echo out the script/code to the console.
Copy the code from the console into your IDE.
Most IDE's perform error checking on the code and highlight errors.
You should be able to see the error almost immediately in your JavaScript/HTML editor.
Had the same issue with a different configuration. This was in an angular factory definition, but I assume it could happen elsewhere as well:
angular.module("myModule").factory("myFactory", function(){
return
{
myMethod : function() // <--- error showing up here
{
// method definition
}
}
});
Fix is very exotic:
angular.module("myModule").factory("myFactory", function(){
return { // <--- notice the absence of the return line
myMethod : function()
{
// method definition
}
}
});
This can also happen in Typescript if you call a function in middle of nowhere inside a class. For example
class Dojo implements Sensei {
console.log('Hi'); // ERROR Identifier expected.
constructor(){}
}
Function calls, like console.log() must be inside functions. Not in the area where you should be declaring class fields.
Typescript for Windows issue
This works in IE, chrome, FF
export const OTP_CLOSE = { 'outcomeCode': 'OTP_CLOSE' };
This works in chrome, FF, Does not work in IE 11
export const OTP_CLOSE = { outcomeCode: 'OTP_CLOSE' };
I guess it somehow related to Windows reserved words