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how to download file using jquery in asp.net core?

I use this code to download file using jquery.
$('#dwnlod').click(function (ee) {
e.preventDefault();
var currentFile = $('#SlideContainer .actv').css('background-image').replace(/^url|[\(\)]/g, '');
alert(currentFile)
document.location.href = currentFile;
});
However, it always does nothing. the reason for this is when I remove e.preventDefault to read the URL I find it distorted.
it rather than the result from alert >>
"https://localhost:660066/Uploads/5c92f430-4aef-41c8-b201-853597935771.jpg"
it displays in a new browser tab >>
https://localhost:660066/Documents/Index/"https://localhost:660066/Uploads/5c92f430-4aef-41c8-b201-853597935771.jpg"
I don't know if I need extra steps with asp.net core routing !!?

It looks like the issue is that currentFile returns a string that is surrounded by quotes and thus the browser is interpreting it as a relative URL (since the scheme isn't at the beginning of the string). Removing the start and end quotes if they exist should get you the behavior you are looking for.

How can I escape a string to ensure that it is a valid string literal in JS source?

I have a Qt application that embeds a web browser (QWebEngineView). I would like to call a javascript function with a string argument from the C++ application. The means of doing this is calling
page()->runJavaScript("setContent(\"hello\");");
This works in simple cases. However, if I try and load, say, a C++ source file and use that as the parameter of setContent, this will break, because I can't simply assemble the string like this:
auto js = QString("setContent(\"%1\");").arg(fileStr);
I tried the following:
fileStr = fileStr.replace('"', "\\\"");
fileStr = fileStr.replace("\n", "\\n");
But apparently this could not escape the string, I get an error when I call this javascript. How can I universally escape a long string with newlines and possible special characters so that I can construct a valid js fragment like this?

So, after some research, I came across QWebChannel which is meant for bi-directional communication between the application and the hosted webpage. The imported qwebchannel.js in the examples can be found here. From there, this is what I did:
In C++:
auto channel = new QWebChannel(this);
page()->setWebChannel(channel);
channel->registerObject("doc", Doc);
In HTML/JS:
new QWebChannel(qt.webChannelTransport,
function(channel) {
var doc = channel.objects.doc; // this is "doc" from the registerObject call
editor.setValue(doc.text);
doc.textChanged.connect(updateText); // textChanged is a signal of the class of doc.
}
);
So, even though this does not directly answer the question, what is presented here can be used to achieve the same effect.

Can I extract comments of any page from https://www.rt.com/ using python3?

I am writing a web crawler. I extracted heading and Main Discussion of the this link but I am unable to find any one of the comment (Ctrl+u -> Ctrl+f . Comment Text). I think the comments are written in JavaScript. Can I extract it?

RT are using a service from spot.im for comments
you need to do make two POST requests, first https://api.spot.im/me/network-token/spotim to get a token, then https://api.spot.im/conversation-read/spot/sp_6phY2k0C/post/353493/get to get the comments as JSON.
i wrote a quick script to do this
import requests
import re
import json
def get_rt_comments(article_url):
spotim_spotId = 'sp_6phY2k0C' # spotim id for RT
post_id = re.search('([0-9]+)', article_url).group(0)
r1 = requests.post('https://api.spot.im/me/network-token/spotim').json()
spotim_token = r1['token']
payload = {
"count": 25, #number of comments to fetch
"sort_by":"best",
"cursor":{"offset":0,"comments_read":0},
"host_url": article_url,
"canonical_url": article_url
}
r2_url ='https://api.spot.im/conversation-read/spot/' + spotim_spotId + '/post/'+ post_id +'/get'
r2 = requests.post(r2_url, data=json.dumps(payload), headers={'X-Spotim-Token': spotim_token , "Content-Type": "application/json"})
return r2.json()
if __name__ == '__main__':
url = 'https://www.rt.com/usa/353493-clinton-speech-affairs-silence/'
comments = get_rt_comments(url)
print(comments)

Yes, if it can be viewed with a web browser, you can extract it.
If you look at the source it is really an iframe that loads a piece of javascript, that then creates a new tag in the document with the source of that script tag loading bundle.js, which really contains the commenting software. This in turns then fetches the actual comments.
Instead of going through this manually, you could consider using for example webkit to create a headless browser that executes the javascript like an ordinary browser. Then you can scrape from that instead of having to manually make your crawler fetch the external resources.
Examples of such headless browsers could be Spynner, Dryscape, or the PhantomJS derived PhantomPy (the latter seems to be an abandoned project now).

Extract URL's directory from path, without file name such as "index.html"

I am looking for plain JavaScript code (no jQuery etc.) to learn the directory path component of my currently loaded page's URL.
For instance, if my page is loaded as "http://localhost/myapp/index.html", I like to end up with "http://localhost/myapp/".
I need this in order to create the path to a different file in the same location, e.g. to "http://localhost/myapp/other.html".

It looks like this does the trick:
var href = window.location.href;
var dir = href.substring(0, href.lastIndexOf('/')) + "/";
Is this a safe method or can this fail with more complex URLs?

Highlighting the comment in the question that helped me:
Phylogenesis's comment:
The simple solution is location.href.replace(/[^/]*$/, ''); then.

One more option to consider, which has the benefit that any query string will not be an issue since window.location.pathname does not pick up the query string.
window.location.origin + window.location.pathname.slice(0, window.location.pathname.lastIndexOf('/'))

A better solution would be
location.href.replace(/\/[^\/]+?\.[^\/]+?$/, '/')

How to escape absolute URI?

In the script: `http://theip.com/something/index.php
I have the following javascript URI:
var uri = '/something/script.php?=' + someDynamicValue
That I pass to a function "loadHTML(url, div)"
someDynamicValue can contain spaces and other symbols which make JQuery crash with $.load().
So, I try to encode uri:
$('#'+div).load(encodeURIComponent(uri));
And gives
http://theip.com/something/%2Fsomething%2Fscript.php%3Fq%3D?_=1399924421585
That is, duplicating the /something (which should be an absolute URL so it should go to http://ip.com/something/script.php)
Now if I do the following:
$('#'+div).load(encodeURIComponent(uri).replace(/%2F/g,'/'));
I get a "good" url but gives 404 Error:
http://theip.com/something/script.php%3Fq%3D?_=1399923477529
So I guess it is taking script.php%3Fq%3D?_=1399923477529 as a literal script name, maybe.
How can I fix it? (Encode the rest of the URL).
Thanks!

You just need to encode the one part that isn't already properly URI encoded:
var uri = '/something/script.php?foo=' + encodeURIComponent(someDynamicValue)
$('#'+div).load(uri);