Is it possible to load a text file via HTML using somthing like the link tag?
I’m sure I have seen this before but couldn’t find any thing.
I am creating a local app and I want to load a CSV data file and don’t want to have to rely on the user choosing the file with a file input.
If you mean like a file on the user's computer...only if the file's contents are saved in a cookie or using localstorage when the file is saved. But if you mean from a website, you can use XMLHttpRequest.
See https://www.w3schools.com/xml/dom_httprequest.asp
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I am building a web app and I would like to show PDF files to my users. My files are mainly stored as byte arrays in the database as they are generated in the backend. I am using the embed element and have found three ways to display a PDF:
Local file path in src attribute: Works, but I need to generate a file from the database byte array, which is not desirable as I have to manage routines to delete them once they are not needed anymore.
Online file path in src attribute: Not possible since my files may not be hosted anywhere but on the server. Also has the same issues as the previous method anyway.
Data as base64 string in src attribute: Current method, but I ran into a problem for larger files (>2MB). Edge and Chrome will not display a PDF when I covert a PDF of this size to a base64 string (no error but the docs reveal that there is a limit for the data in the src attribute). It works on Firefox but I cannot have my users be restricted to Firefox.
Is there any other way to transmit valid PDF data from a byte array out of the database without generating a file locally?
You have made the common mistake of thinking of URLs and file paths as the same thing; but a URL is just a string that's sent to the server, and some content is sent back. Just as you wouldn't save an HTML file to disk for every dynamic page on the site, you don't have to write to the file system to display a dynamic PDF.
So the solution to this is to have a script on your server that takes the identifier of a PDF in your system, maybe does some access checking, and outputs it to the browser.
For example, if you were using PHP, you might write the HTML with <embed src="/loadpdf.php?id=42"> and then in loadpdf.php would write something like this:
$pdfContent = load_pdf_from_database((int)$_GET['id']);
header('Content-Type: application/pdf');
echo $pdfContent;
Loading /loadpdf.php?id=42 directly in the browser would then render the PDF just the same as if it was a "real" file, and embedding it should work the same way too.
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 using a HTML web-page, i don't want to use PHP coding.
I am trying to find some code that will allow me to upload a file and place it in a specified directory. How would i do that.
input type="file", allows me to specify a file but what code allows me to move or copy that file to another location.
It's impossible to oparte on upload file without server-side technology (like php), sorry...
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)
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.