I am facing problem in HTML 5. I need to statically load data into web page from local saved files. Up to now, I have been only able to load data via < input type="file" id="fileinput" / > but I want to load data from static location, which never changes. How to do that? And is there any way how to determine, whether some local file was changed from previous version?
Thanks
no, this isn't possible if by 'local', you mean a file at /home/waypoint/somefile.txt. You can make a 'link' with the filesystem api (if you selected it in an input field, for instance), which is valid to do computations with it (to read it, write to it, display it in img,etc). But it is deleted/unvalid, as soon as the window closes. If you could just magically "read" any local file via javascript which resides on the file system, who would stop google to read out your /etc/passwd file?
if your local computer is also your server and therefor your server-side code has access to the local file /home/waypoint/somefile.txt, your app can get it via ajax. Checking if the file exists, would be done the same way.
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we need to develop an application similar to the below
On the web page user is asked to select the parameters which are present in a Map<String,Boolean>. Once the user selects his choice of parameters then this Map is saved in a .DAT file. Right now I am saving it in C:/Users/Application. But I want the user to choose which directory he wants to save. I was tempted to use <input type="file".....> but it needs a file in the directory.
Is there any way that the user can specify his own directory where this .DAT file is saved.
Something similar to SaveAs..
A webpage cannot choose where the user will download a file that is returned. For some file types, the browser might even show the file instead of downloading it (e.g. PDF file).
I am wondering if I can have a webpage where I can tell it to grab my file and put it in a directory, such as: "http://example.ex/folder". Meaning the file I provided is put into the "folder" folder.
Overall process:
Button says: "Import file"
I select a file, and my file is "text.txt"
It takes my file "text.txt" and adds it to the local system/directory of the website.
You can do this using JQuery File Upload and then adding a backend service that captures the file and saves it.
For example, here is a repository that has a basic Python (Flask) server integrated with JQuery File Upload that will take an uploaded file and place it on the server:
https://github.com/ngoduykhanh/flask-file-uploader
I'd put the rest of the code here, but it is a lot - and requires HTML, JavaScript and a back-end language (like Python).
Here is the documentation on JQuery File Upload: https://github.com/blueimp/jQuery-File-Upload
As a word of caution, DO NOT TRUST ANYTHING UPLOADED TO YOUR SERVER. Meaning, do not put it out on the open internet without some sort of authentication or checks in place to make sure only files you intend are uploaded. Otherwise, people will find it and upload scripts turning your device into a Bitcoin miner, spam relay, or bot host.
Instead of doing it this way, why not use SFTP to upload it to your server to host? At least that way you can lock down access.
I am building a simple editor-type application in react-redux, and I want to mimic the operation of downloading and uploading json files for saving and loading data - entirely client side. The server side does not need the data. Local storage may be too small, and it would be nice to provide the user the data in a portable file they could upload on a new machine. Is this even possible, and if so how?
Using a blob file.
You can set the content of a new file which is temp and local, then trigger a click event to download the file.
duplicate answer here and here
File input allows user to access a local file from browser. Is it possible to load a local file given by file input, modify it and save it back to same local file? I know that HTML5 allows creating writeable filesystem, but basically it seems to be abstract directory.
For security reasons, I don't think the browser can overwrite the local file. Using the File-System API you could only copy the contents of the local file to the sandboxed File-System API directory(found under various obfuscated file names). All manipulation/saving would be done in AppData.
Perhaps displaying the modified image on the screen, right click, save-as to the given file location would also be suitable? (other than that I think you have to upload the image to a server and download it back again)
:image => StorageRoom::Image.new_with_filename(path)
I have to get the path of the image. So far i have specified the path manually and it worked and now i have put in heroku but it shows Load Error - No such file present.
How can i get the path value of the local system using browse button.
Your problem may not be related to path names, but to the fact that Heroku has a read-only file system. If you try to write files onto disk in a Heroku app, it simply doesn't work -- the file will not be saved.
The exception is the "temp" directory. You can save files there, but they are not guaranteed to persist for longer than the duration of a single request.
Is the file you are trying to open actually saved in your Git repo? If so, it will be on the disk in your Heroku app, and you should be able to open it.
To see what the filesystem layout looks like on your Heroku instance, you can create a controller method like:
render :inline => Dir['**/*'].inspect
File.expand_path
Reference : http://saaridev.blogspot.com/2006/11/ruby-finding-absolute-path-of-running.html
You don't need the full path. As far as file path in the client machine is concerned for file uploads, the path is irrelevant as it poses security risks for the user.
Most modern browsers don't send the file path for file uploads. You could get the path using Javascript or Flash but still I don't see the logic behind doing this.
When a user clicks on the submit button the browser should at least send you the file name with the file data together with a bunch of other information like the mime type. Your web server would either write the file to disk or process it in memory assuming you have near infinite memory resources. Look at the RFC 1867 for file uploads for more on this.