How do I read in FILE contents in QML? - qt

Question

I just need something similar to Fstream to read file IO in QML. Why is there no file IO?

Answer 1

If your file is plain text you can use XMLHttpRequest. For example:
var xhr = new XMLHttpRequest;
xhr.open("GET", "mydir/myfile.txt");
xhr.onreadystatechange = function() {
if (xhr.readyState == XMLHttpRequest.DONE) {
var response = xhr.responseText;
// use file contents as required
}
};
xhr.send();

Answer 2

I know this is old question but you might be still interested in answer.
Here it is: Reading a line from a .txt or .csv file in qml (Qt Quick)
In short, you have here explained how to read files in QML: http://www.developer.nokia.com/Community/Wiki/Reading_and_writing_files_in_QML
All you need is to extend QML with C++.

Answer 3

QML has no built-in file I/O. But - judging from the tone of your post - you already knew that.
How do I read in FILE contents in QML?
You can extend QML's functionalities using C++.
The Getting Started Programming with QML tutorial from the Qt Reference Documentation shows you how to build a text editor. This includes file I/O using C++.
Why is there no file I/O?
Because QML is based on JavaScript, and JavaScript has no built-in file I/O either.
QML is designed as an (easy) way to build a user interface. You need an actual program to do the rest.

Answer 4

There is built-in file I/O available for QML with the Felgo SDK (formerly V-Play) FileUtils. It works cross-platform on desktop, iOS and Android. More info and examples are also in the latest blog post.
It looks like this:
var documentsData = fileUtils.readFile("subfolder/file.json")

Answer 5

function readConfigFile() {
var xhr = new XMLHttpRequest;
var configaddress = "File:///" + root + "/webconfig.txt" //root = "c:/folder/file.ini";
console.log(configaddress);
xhr.open("GET", configaddress);
xhr.onreadystatechange = function() {
if (xhr.readyState == XMLHttpRequest.DONE) {
var response = xhr.responseText;
var js = JSON.parse(response)
if (js.address != "") {
service_address = js.address
}
// use file contents as required
}
};
xhr.send();
}

Answer 6

What do you want to read the file for?... if its simple data.. then you are probably better off using QML Offline storage API. Look for that section here.
If you want to deploy a db with your application read this conversation.
If you really want to read the file still, learn C++ and expose your code to QML. That, then, is beyond the scope of my answer.