Is there a way to download a canvas image to a file folder without a prompt showing up? I have found solutions requiring a prompt where you name the file, but I have not found any solutions where you can dynamically name the image and save to a local file. I am very new to front-end development, so I am not entirely familiar with Node.js or JQuery/PHP/Ajax. I have found solutions using these but they have ended up still using prompts.
In general, this is a security feature.
You don't want a site you browsing to save files to your computer silently. They can possibly contain a malicious code for example, or override an existing file. Thus, as a security feature the browsers are asking you to name the file you will save.
There is a way to name the files thou, so you don't need to present the user with generic file name.
On How to do that - it really depends what are you using to do it..
In your situation - if those are log files you want to save - you can send them back to the server. That can be easily done.
Related
I have a web application that receives a simple text file, but I need this file to be downloaded to a specific path. Meaning, when the application receives a text file, it will always be downloaded to a specific folder (for example, to C:\MyFolder). If it isn't possible, then I need to copy the file from where user has chosen to my folder.
This application is based on JavaScript.
JavaScript cannot exert any control over my (the visitor's) local filesystem. I remain in complete control of where my downloaded files go, what they are named, and indeed whether I even want to download them in the first place.
Sorry, but the best you can do is inform your users where to put the file you're offering for download. You cannot use JavaScript to choose the destination yourself.
You should be able to do this using a Java applet assuming that you have signed it. The user would be asked to allow your code to run and if allowed, you could do whatever you want: Including downloading a file to a specific location.
I have a web application that receives a simple text file, but I need this file to be downloaded to a specific path. Meaning, when the application receives a text file, it will always be downloaded to a specific folder (for example, to C:\MyFolder). If it isn't possible, then I need to copy the file from where user has chosen to my folder.
This application is based on JavaScript.
JavaScript cannot exert any control over my (the visitor's) local filesystem. I remain in complete control of where my downloaded files go, what they are named, and indeed whether I even want to download them in the first place.
Sorry, but the best you can do is inform your users where to put the file you're offering for download. You cannot use JavaScript to choose the destination yourself.
You should be able to do this using a Java applet assuming that you have signed it. The user would be asked to allow your code to run and if allowed, you could do whatever you want: Including downloading a file to a specific location.
Hello! My question is about javascript.
I want to
1. ask a user to select a directory
2. then write my bunch of files to it (probably with creating sub-directories) without interaction with user
How can I do this? And can I?
I am new in javascript and I hope for your help.
PS.
I've heard about ability to ask a user to select a path by save file dialog and then save data to selected file, but i want to ask a user once for selecting a directory and then create a bunch of files in it without bothering a user for each one.
Javascript alone doesn't have any way to access the local computer's file system for WRITE purposes. Period.
However, Downloadify, by Doug Neiner, was built for this purpose and uses a combination of Javascript and the Flash library.
It needs Flash 10 to work.
Alternately, you can install apache onto the computer (or better yet, a full stack like XAMPP or WAMP/MAMP/LAMP) and use PHP (with javascript/ajax) to write files onto the local file system. However, this means that the website must also be hosted locally. Probably your best bet is Downloadify
Resources:
https://github.com/dcneiner/Downloadify
How to create xml file with jquery
Save content using Jquery? Write to file
Saving to server-side file using AJAX
I am wondering if there is any method of reading file on the client side with javascript given the file name and path. I am aware of the method of reading through: input type="file".
What I mean is without opening up a file browser and selecting the file, just reading it with filename, like fopen.
If not an other method, how to instantiate a File object in javascript from filename and path?
Seeing the answers I thought of briefing a bit more on my purpose.
I am not really making a webpage. I am using browser just as a software that is available on any system. The html pages will all be local. I am doing this way be so that I have the advantage of the power of js. Given this situation is there any way to set permission flags that will let it read files?
Thank you.
There's the Drag 'n Drop API which would be the other option in reading files using JS
There will always be hurdles so that your code will not directly read from the client's filesystem. This is designed for privacy and security purposes.
Extensions/Plugins - sandboxing will be your enemy, limiting file system access
Java Applet - Needs a signed certificate to read the filesystem. A self-signed certificate will generate the "Will You Trust This Applet" prompt which would act as the security prompt.
Input type=file - gives the user the option to select the files or not
drag and drop - gives the user the option to drag in files or not
XHR - Same Origin Policy will block you, especially if you are executing the page locally and not on a server.
JSONP - Since this bypasses the SOP, however, your file should be in JSONP format.
I found solution to my problem, here it is...
It is true that we have restriction with javascript that whenever the user or the page requests for a file it has to go through that extra window that pops up,
but if all the files that you may request are inside a known folder then you can rather ask the user to point the zipped folder instead.
One can use tools like zip.js for opening a file that one needs in the zipped folder.
Thank you :)
I want to allow a web site users to be able to download files from my site, but with the help of a client-side downloader with an ability to continue an interrupted download.
For example, I want to sent a person a file with a size of 30+ Meg. I want the user to have the best downloading experience, so I can't afford him downloading 25 Meg and then getting the download dropped due to the network problems on his side.
Therefore, I want to have a javascript downloader rendered on a download page, that will show the actual client-side file delivery, and when it is downloaded, to give an ability to a user to save the file.
Or is it not possible due to the fact that javascript won't be able to open a save file dialog and save to a file system?
I'm afraid that is not possible with JavaScript and that's why:
To continue downloading from the certain point you should send to the server the position number to start downloading from. And as JavaScript has no access to local file system, you can't get that position.
UPD: it seems that I was too hurrying with the reply.
The file size can be gotten using the HTML5 File API and after getting the file size you can pass it to the server which should support the partial downloading.
But anyway, after downloading another part of the file you should sew two pieces together in some way; standard web browser dialog will only suggest to overwrite the file.
UPD2: to work with files in some Internet Explorers you can use FileSystemObject:
var fso;
fso = new ActiveXObject("Scripting.FileSystemObject");
I'd look into making a plugin or extension. Like those DownloadThemAll extensions for firefox and Google chrome. Another alternative would be to use Flash, either alone or integrating it with javascript like hinted here: http://www.communitymx.com/content/article.cfm?cid=0922A