Yes, open the contextmenu in the console, and remove the check at `Log XMLHttpRequests`.

You can still inspect the network traffic at the Network tab.


There is some workaround posted in chromium issue tracker http://code.google.com/p/chromium/issues/detail?id=15472

Which version of chrome you are using? In my console there is checkbox to enable or diable log XMLHTTPRequests I am using 17.0.963.79

&gt; **Possible Duplicate:**  
&gt; [&amp;ldquo;ValueError: zero length field name in format&amp;rdquo; error in Python 3.0,3.1,3.2](https://stackoverflow.com/questions/5446964/valueerror-zero-length-field-name-in-format-error-in-python-3-0-3-1-3-2)  

&lt;!-- End of automatically inserted text --&gt;

I have spent hours trying to solve this problem but to no avail. I read [this guide](http://docs.python.org/release/3.1.3/library/string.html).
I haven&#39;t found any examples how to do what I need. 

When I run the script I get this error (partly omitted):&lt;br&gt;

    Traceback (...):
       [...]
       output.write(&quot;{: &gt; 026,.18e} {: &gt; 026,.18e}\n&quot;.format(x,y))
    ValueError: zero length field name in format.

The code is written in python 2.6 or 2.7 but I run python 3.1. How would I need to change output format so that it would work? 

    def f(x,y,a = 0.01):
        return y/(a+x)-y**3

    def ekspEuler(N,dat):
        output = open(dat,&quot;w&quot;)
        h = 3.0/N
        x,y = 0,1 #zac.pogoj

        for i in range(1,N+2):
            output.write(&quot;{: &gt; 026,.18e} {: &gt; 026,.18e}\n&quot;.format(x,y))
            y += h*f(x,y)
            x = i*h
        output.close()

Thanks for your help.

ValueError: zero length field name in format python

Is there a simple alternative in PostgreSQL to this statement produced in Oracle?

    select table_name from user_tab_columns
    where table_name = myTable and column_name = myColumn;

I am then testing whether the query returns anything so as to prove the column exists.

I am aware that using psql I can find these out individually but this is required to produce a result in a program I am writing to validate that a requested attribute field exists in my database table.

How can I test if a column exists in a table using an SQL statement

Is there a way to hide the `&quot;XHR finished loading&quot;` messages in the console?

When loading external data, console says: XHR finished loading

<p>Is there a way to hide the <code>"XHR finished loading"</code> messages in the console?</p>


Is it possible to make an ajax request inside another ajax request?
because I need some data from first ajax request to make the next ajax request.

First I&#39;m using Google Maps API to get LAT &amp; LNG, after that I use that LAT &amp; LNG to request Instagram API (search based location).

Once again, is this possible, and if so how?

    $(&#39;input#search&#39;).click(function(e) {
		e.preventDefault();
		var source = $(&#39;select[name=state] option:selected&#39;).text()+&#39; &#39;+$(&#39;select[name=city] option:selected&#39;).text()+&#39; &#39;+$(&#39;select[name=area] option:selected&#39;).text();
		var source = source.replace(/ /g, &#39;+&#39;);
		if(working == false) {
			working = true;
			$(this).replaceWith(&#39;&lt;span id=&quot;big_loading&quot;&gt;&lt;/span&gt;&#39;);
			$.ajax({
				type:&#39;POST&#39;,
				url:&#39;/killtime_local/ajax/location/maps.json&#39;,
				dataType:&#39;json&#39;,
				cache: false,
				data:&#39;via=ajax&amp;address=&#39;+source,
				success:function(results) {
				// this is where i get the latlng
				}
			});
		} else {
			alert(&#39;please, be patient!&#39;);
		}
	});

jQuery Ajax Request inside Ajax Request

I would like to add a custom header to an AJAX POST request from jQuery.

I have tried this: 

    $.ajax({
    	type: &#39;POST&#39;,
    	url: url,
    	headers: {
    		&quot;My-First-Header&quot;:&quot;first value&quot;,
    		&quot;My-Second-Header&quot;:&quot;second value&quot;
    	}
    	//OR
    	//beforeSend: function(xhr) { 
    	//	xhr.setRequestHeader(&quot;My-First-Header&quot;, &quot;first value&quot;); 
    	//	xhr.setRequestHeader(&quot;My-Second-Header&quot;, &quot;second value&quot;); 
    	//}
    }).done(function(data) { 
    	alert(data);
    });

When I send this request and I watch with FireBug, I see this header: 

&gt;    OPTIONS xxxx/yyyy HTTP/1.1&lt;br/&gt;
    Host: 127.0.0.1:6666&lt;br/&gt;
    User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:11.0) Gecko/20100101 Firefox/11.0&lt;br/&gt;
    Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8&lt;br/&gt;
    Accept-Language: fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3&lt;br/&gt;
    Accept-Encoding: gzip, deflate&lt;br/&gt;
    Connection: keep-alive&lt;br/&gt;
    Origin: null&lt;br/&gt;
    Access-Control-Request-Method: POST&lt;br/&gt;
    **Access-Control-Request-Headers: my-first-header,my-second-header**&lt;br/&gt;
    Pragma: no-cache&lt;br/&gt;
    Cache-Control: no-cache&lt;br/&gt;

Why do my custom headers go to `Access-Control-Request-Headers`: 

&gt;    Access-Control-Request-Headers: my-first-header,my-second-header

I was expecting a header values like this: 

&gt;    My-First-Header: first value&lt;br/&gt;
&gt;    My-Second-Header: second value

Is it possible?

Access Control Request Headers, is added to header in AJAX request with jQuery

I&#39;m making an `Ajax.request` to a remote PHP server in a [Sencha Touch][1] 2 application (wrapped in [PhoneGap][2]).

The response from the server is the following:

&gt; XMLHttpRequest cannot load http://nqatalog.negroesquisso.pt/login.php. Origin `http://localhost:8888` is not allowed by Access-Control-Allow-Origin.

How can I fix this problem?

  [1]: https://en.wikipedia.org/wiki/Sencha_Touch
  [2]: http://en.wikipedia.org/wiki/PhoneGap


Origin is not allowed by Access-Control-Allow-Origin

The service API I am consuming has a given GET method that requires the data be sent in the body of the request.  

The data required in the body is a list of id&#39;s separated by hypen and could potentially be very large and thus it must be sent in the body otherwise it will likely foobar somewhere in the browsers/proxies/webservers etc chain. Note I don&#39;t have control over the service or API so please don&#39;t make suggestions to change it.

I am using the following jQuery code however observing the request/response in fiddler I can see that the &quot;data&quot; I am sending is ALWAYS converted and appended to the query string despite me setting the &quot;processData&quot; option to false...

    $.ajax({
       url: &quot;htttp://api.com/entity/list($body)&quot;,
       type: &quot;GET&quot;,
       data: &quot;id1-id2-id3&quot;,
       contentType: &quot;text/plain&quot;,
       dataType: &quot;json&quot;,
       processData: false, // avoid the data being parsed to query string params
       success: onSuccess,
       error: onError
    });

Anyone know how I can force the &quot;data&quot; value to be sent in the body of the request? 
Any assistance is appreciated, thanks in advance.

How to send data in request body with a GET when using jQuery $.ajax()

**jQuery v1.7.2**

I have this funcion that is giving me the following error while executing :

    Uncaught TypeError: Illegal invocation

Here&#39;s the function :

	$(&#39;form[name=&quot;twp-tool-distance-form&quot;]&#39;).on(&#39;submit&#39;, function(e) {
		e.preventDefault();
		
		var from = $(&#39;form[name=&quot;twp-tool-distance-form&quot;] input[name=&quot;from&quot;]&#39;);
		var to = $(&#39;form[name=&quot;twp-tool-distance-form&quot;] input[name=&quot;to&quot;]&#39;);
		var unit = $(&#39;form[name=&quot;twp-tool-distance-form&quot;] input[name=&quot;unit&quot;]&#39;);
		var speed = game.unit.speed($(unit).val());
		
		if (!/^\d{3}\|\d{3}$/.test($(from).val()))
		{
			$(from).css(&#39;border-color&#39;, &#39;red&#39;);
			return false;
		}
		
		if (!/^\d{3}\|\d{3}$/.test($(to).val()))
		{
			$(to).css(&#39;border-color&#39;, &#39;red&#39;);
			return false;
		}
		
		var data = {
			from : from,
			to : to,
			speed : speed
		};
		
		$.ajax({
			url : base_url+&#39;index.php&#39;,
			type: &#39;POST&#39;,
			dataType: &#39;json&#39;,
			data: data,
			cache : false
		}).done(function(response) {
			alert(response);
		});
		
		return false;
	});

If I remove `data` from ajax call, it works .. any suggestions?

Thanks!

jQuery - Illegal invocation

I want to force the Chrome debugger to break on a line _via code_, or else using some sort of comment tag such as something like `console.break()`.


How to set a JavaScript breakpoint from code in Chrome?

What are the differences between socket.io and websockets in
    node.js?  
Are they both server push technologies?
The only differences I felt was,

1. socket.io allowed me to send/emit messages by specifying an event name.

2. In the case of socket.io a message from server will reach on all clients, but for the same    in websockets I was forced to keep an array of all connections and loop through it to send messages to all clients.

Also,
I wonder why web inspectors (like Chrome/firebug/fiddler) are unable to catch these messages (from socket.io/websocket)  from server?

Please clarify this.

Differences between socket.io and websockets

I have created some fairly elaborate DOM elements with an :after pseudo-element, and I&#39;d like to be able to inspect and tweak them in either Chrome Inspector or Firebug or equivalent.

Despite this feature being mentioned in [this WebKit/Safari blog post](http://www.webkit.org/blog/1091/more-web-inspector-updates/) (dated 2010), I can&#39;t find this feature at all in either Chrome or Safari. Chrome does at least have checkboxes to inspect :hover, :visited and :active states, but :before and :after are nowhere to be seen.

Additionally, [this blog post](http://meyerweb.com/eric/thoughts/2009/11/03/pseudo-phantoms/) (dated 2009!) mentions this capability exists in the IE dev tools, but I&#39;m currently using Mac OS, so this is no help to  me. Additionally, IE is not a browser I&#39;m primarily targeting.

Is there any way of inspecting these pseudo-elements?

EDIT: In addition to being wrong about Firebug being unable to inspect these elements, I&#39;ve found Opera to be pretty good at Inspecting :before and :after elements out of the box.

How can I inspect and tweak :before and :after pseudo-elements in-browser?

I am doing a console.log statement in my javascript in order to log a javascript object. I&#39;m wondering if there&#39;s a way, once that&#39;s done - to copy that object as javascript code. What I&#39;m trying to do is convert an object that was created using ajax to parse an xml feed into a static javascript object so that a file can run locally, without a server. I&#39;ve included a screenshot of the object in the chrome inspector window so you can see what I&#39;m trying to do.![enter image description here][1]


  [1]: http://i.stack.imgur.com/RsxAB.png

Javascript / Chrome - How to copy an object from the webkit inspector as code

Is there a way I can simulate various connection speeds from within Chrome?

I need to be able to check http://localhost with varying speeds.

I know there are standalone applications that can do this, but I&#39;d rather do this inside Chrome.

Simulate limited bandwidth from within Chrome?

&lt;br/&gt;
I have a console application in which I want to write the name of a file.

```
Process.Start(&quot;blah.bat&quot;);
```

Normally, I would have something like that in windows application by writing the name of the file `&#39;blah.bat&#39;` to **Settings** file in **Properties**.&lt;br/&gt;
However, here I didn&#39;t find any *Settings* file and I added an **app.config** for the same purpose.&lt;br/&gt;

I am not sure what to write here in **app.config**, that would lead to me to achieve similar thing as in ***Windows Forms***.&lt;br/&gt;

For eg: In windows forms. `Process.Start(Properties.Settings.Default.BatchFile);`&lt;br/&gt;
where `BatchFile` is a string in settings file in Properties.

App.Config file in console application C#

I have tried `put -r directory/*`, which only uploaded the files and not folders. Gave me the error, cannot `Couldn&#39;t canonicalise`. 

Any help would be greatly appreciated.

How can I upload an entire folder, that contains other folders, using sftp on linux?

I want to see what happens in the iOS Simulator if I&#39;m not testing the app in Xcode.

For example, if I open a link in the Safari simulator, see what happens in the console,
or if I install a web-app, see the links that I&#39;m pressing in console.

How can I do this?

I want to see it in Xcode or Terminal, but it&#39;s not a problem if I need to use another bit of software.

How can I get the console logs from the iOS Simulator?

I just started out with Google Chrome extensions and I can&#39;t seem to log to console from my background js. When an error occurs (because of a syntax error, for example), I can&#39;t find any error messages either.

My manifest file:

    {
      &quot;name&quot;: &quot;My First Extension&quot;,
      &quot;version&quot;: &quot;1.0&quot;,
      &quot;manifest_version&quot;: 2,
      &quot;description&quot;: &quot;The first extension that I made.&quot;,
      &quot;browser_action&quot;: {
        &quot;default_icon&quot;: &quot;icon.png&quot;
      },
      &quot;background&quot;: {
        &quot;scripts&quot;: [&quot;background.js&quot;]
      },
      &quot;permissions&quot;: [
        &quot;pageCapture&quot;,
        &quot;tabs&quot;
      ]
    }


background.js:

    alert(&quot;here&quot;);
    console.log(&quot;Hello, world!&quot;)

When I load the extension, the alert comes up but I don&#39;t see anything being logged to console. What am I doing wrong?

Accessing console and devtools of extension&#39;s background.js

I am writing a script and I want to output text messages to the console with different colors depending on conditions. For example: RED for errors and BLUE for warnings, etc.

I am using RStudio.

Is there a way to output text to the R console in color

**Here&#39;s a noodle scratcher.**

**Bearing in mind we have HTML5 local storage and xhr v2 and what not. I was wondering if anyone could find a working example or even just give me a yes or no for this question:**

Is it possible to Pre-size an image using the new local storage (or whatever), so that a user who does not have a clue about resizing an image can drag their 10mb image into my website, it resize it using the new localstorage and THEN upload it at the smaller size.

I know full well you can do it with Flash, Java applets, active X... The question is if you can do with Javascript + Html5.

Looking forward to the response on this one.

Ta for now.

HTML5 Pre-resize images before uploading

I have a little problem understanding `XMLHttpRequest`&#39;s handlers. [The specification says this about the `onerror` handler][1]:

&gt; `error`   [Dispatched ... ] When the request has failed.
&gt;
&gt; `load`    [Dispatched ... ] When the request has successfully completed.

The problem is, what does it mean that &quot;the request has failed&quot;. That could be

- the request couldn&#39;t be issued at all (eg. Connection refused and such errors), or
- the above plus the server returned an error code (eg. 404)

Also, I&#39;d like to know whether it means `onerror` and `onload` should never fire simultaneously.

[This reference][2] indicates the `onerror` handler should be executed depending on the `status` code and `onload` depending on `readyState`. That would indicate they are not mutually exclusive, however, I don&#39;t think this is an authoritative information.

I&#39;m asking because using the latest Opera snapshot, I found `onload` is fired even on 404 status code. I know testing `status` is a sure bet, but I&#39;d like to know whether it&#39;s something I have to do per specification or just a workaround for a bug in Opera.


  [1]: http://www.w3.org/TR/XMLHttpRequest/#event-xhr-error
  [2]: http://www.javascriptkit.com/jsref/ajax.shtml

When should XMLHttpRequest&#39;s onerror handler fire

I am stuck with this CORS problem, even though I set the server (nginx/node.js) with the appropriate headers.

I can see in Chrome Network pane -&gt; Response Headers:

    Access-Control-Allow-Origin:http://localhost

which should do the trick.

Here&#39;s the code that I now use to test:

    var xhr = new XMLHttpRequest();
    xhr.onload = function() {
       console.log(&#39;xhr loaded&#39;);
    };
    xhr.open(&#39;GET&#39;, &#39;http://stackoverflow.com/&#39;);
    xhr.send();

I get

&gt; XMLHttpRequest cannot load http://stackoverflow.com/. Origin http://localhost is not allowed by Access-Control-Allow-Origin.

I suspect it&#39;s a problem in the client script and not server configuration...


Why does my http://localhost CORS origin not work?

I want to send a few variables and a string with the `POST` method from JavaScript. 

I get the string from the database, and then send it to a PHP page. I am using an `XMLHttpRequest` object.

The problem is that the string contains the character `&amp;` a few times, and the `$_POST` array in PHP sees it like multiple keys.

I tried replacing the `&amp;` with `\&amp;` with the `replace()` function, but it doesn&#39;t seem to do anything.

Can anyone help?

**The javascript code and the string looks like this:**

    var wysiwyg = dijit.byId(&quot;wysiwyg&quot;).get(&quot;value&quot;);
	var wysiwyg_clean = wysiwyg.replace(&#39;&amp;&#39;,&#39;\&amp;&#39;);

	var poststr = &quot;act=save&quot;;

	poststr+=&quot;&amp;titlu=&quot;+frm.value.titlu;
	poststr+=&quot;&amp;sectiune=&quot;+frm.value.sectiune;
	poststr+=&quot;&amp;wysiwyg=&quot;+wysiwyg_clean;
	poststr+=&quot;&amp;id_text=&quot;+frm.value.id_text;

	xmlhttp.open(&quot;POST&quot;,&quot;lista_ajax.php&quot;,true);
	xmlhttp.setRequestHeader(&quot;Content-type&quot;,&quot;application/x-www-form-urlencoded&quot;);
	xmlhttp.send(poststr);


**The String is:**

     &lt;span class=&quot;style2&quot;&gt;&amp;quot;Busola&amp;quot;&lt;/span&gt;

How can I send the &quot;&amp;&quot; (ampersand) character via AJAX?

I have a customizable form element on a page from a library. I want to see what javascript events are fired when I interact with it because I am trying to find out which event handler to use.

How do I do that using Chrome Web Developer?

How do I view events fired on an element in Chrome DevTools?

EVERY SINGLE TIME I view an object in the console I am going to want to expand it, so it gets tiresome to have to click the arrow to do this EVERY SINGLE TIME :)  Is there a shortcut or setting to have this done automatically?

Is there a way to auto expand objects in Chrome Dev Tools?

As of version 19, Chrome&#39;s Web Inspector has an experimental feature called &quot;snippets support&quot;. Here is how to activate it:

1. Open chrome:flags, enable &quot;Developer Tools experiments&quot;, restart.

2. Open Web Inspector (Developer Tools), hit the settings gear icon in the lower right corner, enable &quot;Snippets support&quot;, restart.

    ![enable snippets support][1]

3. Open the Scripts panel, click the &quot;navigator tree&quot; icon on the left, and find an empty Snippets tab.

    ![snippets tab][2]

My question is: **What can I use this for? How can I populate this with snippets?**

  [1]: http://i.stack.imgur.com/Thsl0.png
  [2]: http://i.stack.imgur.com/01MI3.png

Content Type	Original Author	Original Content on Stackoverflow
Question	Kriem	View Question on Stackoverflow
Solution 1 - Ajax	Rob W	View Answer on Stackoverflow
Solution 2 - Ajax	Sandeep Manne	View Answer on Stackoverflow

When loading external data, console says: XHR finished loading

Ajax Problem Overview

Ajax Solutions

Solution 1 - Ajax

Solution 2 - Ajax

How can I test if a column exists in a table using an SQL statement

ValueError: zero length field name in format python

Attributions