I am sending data via ajax to post in mysql. In this context how to inlude image file contents ?
If i use like :
var formData = document.getElementById("img_file");
alert(formData.files[0]);
, i get error . Note : img_file is the id of the file dom.
Any idea about this ?
You can use javascript FileReader for this purpose. Here is a sample code demonstration.
<html>
<body>
<input type="file" id="fileinput" />
<div id="ReadResult"></div>
<script type="text/javascript">
function readSingleFile(evt) {
//Retrieve the first (and only!) File from the FileList object
var f = evt.target.files[0];
if (f) {
var r = new FileReader();
r.onload = function (e) {
var contents = e.target.result;
document.getElementById("ReadResult").innerHTML = contents;
}
r.readAsText(f);
} else {
alert("Failed to load file");
}
}
document.getElementById('fileinput').addEventListener('change', readSingleFile, false);
</script>
</body>
</html>
Find more details here.
i think it may help you.
$('#image').change(function () {
$("#add").attr("disabled", true);
var img = this.files[0];
var reader = new FileReader;
reader.readAsDataURL(img);
reader.onload = function (e) {
var file = new Image;
file.src = e.target.result;
file.onload = function () {
$("#height").text(file.height);
$("#width").text(file.width);
$("#imageprev").attr("src", file.src);
$("#upld").removeAttr("disabled");
}
}
});
Related
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.8.0/jszip.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/xlsx/0.8.0/xlsx.js"></script>
<script>
var ExcelToJSON = function() {
this.parseExcel = function(file) {
var reader = new FileReader();
reader.onload = function(e) {
var data = e.target.result;
var workbook = XLSX.read(data, {
type: 'binary'
});
workbook.SheetNames.forEach(function(sheetName) {
// Here is your object
var XL_row_object = XLSX.utils.sheet_to_row_object_array(workbook.Sheets[sheetName]);
var json_object = JSON.stringify(XL_row_object);
console.log(JSON.parse(json_object));
jQuery('#xlx_json').val(json_object);
})
};
reader.onerror = function(ex) {
console.log(ex);
};
reader.readAsBinaryString(file);
};
};
function handleFileSelect(evt) {
var files = evt.target.files; // FileList object
var xl2json = new ExcelToJSON();
xl2json.parseExcel(files[0]);
}
</script>
<form enctype="multipart/form-data">
<input id="upload" type=file name="files[]">
</form>
<textarea class="form-control" rows=35 cols=120 id="xlx_json"></textarea>
<script>
document.getElementById('upload').addEventListener('change', handleFileSelect, false);
</script>
Hello, from the above snippet of code, I am trying to read in the variables from each parsed row in the excel file (the code takes an excel file and prints all the data by row), the best way to describe what I want would probably be something like this in c++(only way I know how to communicate).
void read(string fileName) {
// assume int a,b,c are already declared
// assuming first row of parsed data is vector
for (int i = 0; i < rows.size(); i++) {
a = vector[i][0];
b = vector[i][1];
c = vector[i][2];
// code for thing I am doing here(doesnt matter)
}
}
Is there something like this in javascript or a different method potentially?
I believe that I figured out the answer to my question.
// to access a specific element, I need to do something like this
var obj = JSON.parse(json_object);
a = obj[0]["value"];
I have an HTML form that is used to upload a file to the server. This works correctly but now I am trying to expand the capability such that I select a tar file that consists of two binary files. Then untar the files and based on certain conditions either upload the first or the second file.
This is what I have done so far
use FileReader to read the tar file as ByteArray
use untar from js-untar to untar both file
I need help to figure out how to take the ByteArray for either files and add then to the FormData so that I can upload them.
Any help would be appreciated.
Here are snippets from my code
HTML Form
<form id="upform" enctype="multipart/form-data"
action="cgi-bin/upload2.cgi">
Firmware file: <input id='userfile' name="userfile" type="file" width=50 >
<input type
="submit" name="submitBtn" value="send file">
</form>
Untar code
function sendData() {
var formData = new FormData(form);
var action = form.getAttribute('action');
filesize = file.files[0].size;
var reader = new FileReader();
reader.onload = function() {
untar(reader.result).then(
function (extractedFiles) { // onSuccess
console.log('success');
formData.delete('userfile');
var reader2 = new FileReader();
reader2.onload = function() {
formData.append('userfile', reader2.result);
upload(formData);
}
var blob = new Blob([extractedFiles[0]], {type : 'multipart/form-data'});
reader2.readAsDataURL(blob);
// var f = URL.createObjectURL(blob);
},
function (err) {
console.log('Untar Error');
}
)
};
reader.readAsArrayBuffer(file.files[0]);
return;
}
function upload(formData) {
var action = form.getAttribute('action');
reqUpload.open('POST', action, true);
reqUpload.onreadystatechange = uploadState;
document.body.style.cursor = "wait";
var ld = document.getElementById("load");
ld.classList.add("loader");
reqUpload.send(formData);
document.getElementById('progress').style.display = "block";
progTimer = setInterval(ping, 10000);
uploadStarted = true;
return;
}
I have a problem with a little site (it's intended to work as a local site) I try to create.
I want it to print text from local txt file onto the page. I want it to display it like this one,
<script type="text/javascript">
var arr = ['Heading 1','Para1','Heading 2','Para2','Heading 3','Para3'];
var result = arr.map((val, i) => i%2===0 ? `<h2>${val}</h2>` : `<p>${val}</p>`).join('');
document.getElementById('test').innerHTML = result ;
</script>
but I want it to do it from a file, like this one
<script>
var fileInput = document.getElementById('inputfile');
fileInput.addEventListener('change', function(e) {
var file = fileInput.files[0];
var reader = new FileReader();
reader.onload = function(e) {
document.getElementById('output').innerText = reader.result;
};
reader.readAsText(file);
});
</script>
I tried to merge them together like this
<script>
var fileInput = document.getElementById('inputfile');
fileInput.addEventListener('change', function(e) {
var file = fileInput.files[0];
var reader = new FileReader();
reader.onload = function(e) {
document.getElementById('output').innerHTML = reader.result.split("\n").map((val, i) => i%2===0 ? <h2>${val}</h2> : <p>${val}</p>).join('');
};
reader.readAsText(file[0]);
});
</script>
But something is still not working right (after choosing the file to read, it does nothing) and I am not sure what am I doing wrong. I am green in javascript, so I would appreciate any help in that matter.
Actually, now that I read that again - the only issue with your example is you were using file[0] instead of file
<input type="file" id="inputfile" />
<p id="output"></p>
<script>
var fileInput = document.getElementById('inputfile');
fileInput.addEventListener('change', function(e) {
var file = fileInput.files[0];
var reader = new FileReader();
reader.onload = function(e) {
document.getElementById('output').innerHTML = reader.result.split("\n").map((val, i) => i%2===0 ? `<h2>${val}</h2>` : `<p>${val}</p>`).join('');
};
reader.readAsText(file); // HERE!
});
</script>
The following code should read the content of a text file which is in the current directory upon load, and display it on the html page. I tried modifying by my self. But it does not give an output. Is there an easier way to get this result using another method? or please help figure out what is wrong with this code?
<html>
<head>
<meta http-equiv='Content-type' content='text/html;charset=UTF-8' >
<script>
function startRead()
{
// obtain input element through DOM
var file = document.getElementById("\\file.txt").files[0]
if(file)
{
getAsText(file);
}
}
function getAsText(readFile)
{
var reader;
try
{
reader = new FileReader();
}catch(e)
{
document.getElementById('output').innerHTML =
"Error: seems File API is not supported on your browser";
return;
}
// Read file into memory as UTF-8
reader.readAsText(readFile, "UTF-8");
// Handle progress, success, and errors
reader.onload = loaded;
reader.onerror = errorHandler;
}
function loaded(evt)
{
// Obtain the read file data
var fileString = evt.target.result;
document.getElementById('output').innerHTML = fileString;
}
function errorHandler(evt)
{
if(evt.target.error.code == evt.target.error.NOT_READABLE_ERR)
{
// The file could not be read
document.getElementById('output').innerHTML = "Error reading file..."
}
}
//Start reading file on load
window.addEventListener("load", startRead() { }, false);
</script>
</head>
<body>
<pre>
<code id="output">
</code>
</pre>
</body>
</html>
Given below is the code which I modified to get the above code. My intention was. As I open the html file it would read the text file which is in the current directory and display the content.
<html>
<head>
<meta http-equiv='Content-type' content='text/html;charset=UTF-8' >
<script>
function startRead()
{
// obtain input element through DOM
var file = document.getElementById("file").files[0];
if(file)
{
getAsText(file);
}
}
function getAsText(readFile)
{
var reader;
try
{
reader = new FileReader();
}catch(e)
{
document.getElementById('output').innerHTML =
"Error: seems File API is not supported on your browser";
return;
}
// Read file into memory as UTF-8
reader.readAsText(readFile, "UTF-8");
// Handle progress, success, and errors
reader.onload = loaded;
reader.onerror = errorHandler;
}
function loaded(evt)
{
// Obtain the read file data
var fileString = evt.target.result;
document.getElementById('output').innerHTML = fileString;
}
function errorHandler(evt)
{
if(evt.target.error.code == evt.target.error.NOT_READABLE_ERR)
{
// The file could not be read
document.getElementById('output').innerHTML = "Error reading file..."
}
}
</script>
</head>
<body>
<input id="file" type="file" multiple onchange="startRead()">
<pre>
<code id="output">
</code>
</pre>
</body>
</html>
Try this snippet, I just tried and it works :)!
Live Demo (With Input File)
var fileInput = document.getElementById('fileInput');
var fileDisplayArea = document.getElementById('fileDisplayArea');
fileInput.addEventListener('change', function(e) {
var file = fileInput.files[0];
var textType = /text.*/;
if (file.type.match(textType)) {
var reader = new FileReader();
reader.onload = function(e) {
var content = reader.result;
//Here the content has been read successfuly
alert(content);
}
reader.readAsText(file);
} else {
fileDisplayArea.innerText = "File not supported!"
}
});
<input type="file" id="fileInput">
Without Input File
Function
function readTextFile(file){
var rawFile = new XMLHttpRequest();
rawFile.open("GET", file, false);
rawFile.onreadystatechange = function ()
{
if(rawFile.readyState === 4)
{
if(rawFile.status === 200 || rawFile.status == 0)
{
var allText = rawFile.responseText;
alert(allText);
}
}
}
rawFile.send(null);
}
And to test it
Test
Notice: I tried it, but it works only in firefox
<html>
<head></head>
<body>
<input type="file" id="openfile" />
<br>
<pre id="filecontents"></pre>
<script type="text/javascript">
document.getElementById("openfile").addEventListener('change', function() {
var fr = new FileReader();
fr.onload = function() {
document.getElementById("filecontents").textContent = this.result;
}
fr.readAsText(this.files[0]);
})
</script>
</body>
</html>
this code works
<script type="text/javascript">
document.getElementById("openfile").addEventListener('change', function(){
var fr= new FileReader();
fr.onload= function(){
document.getElementById("readfile").textContent=this.result;
}
fr.readAsText(this.files[0]);
})
</script>
<html>
<head>
<title>reading file</title>
</head>
<body>
var input = document.getElementById("myFile");
var output = document.getElementById("output");
input.addEventListener("change", function () {
if (this.files && this.files[0]) {
var myFile = this.files[0];
var reader = new FileReader();
reader.addEventListener('load', function (e) {
output.textContent = e.target.result;
});
reader.readAsBinaryString(myFile);
}
});
<input type="file" id="myFile">
<hr>
<textarea style="width:500px;height: 400px" id="output"></textarea>
<input type="file" id="myFile">
<hr>
<!--<div style="width: 300px;height: 0px" id="output"></div>-->
<textarea style="width:500px;height: 400px" id="output"></textarea>
<script>
var input = document.getElementById("myFile");
var output = document.getElementById("output");
input.addEventListener("change", function () {
if (this.files && this.files[0]) {
var myFile = this.files[0];
var reader = new FileReader();
reader.addEventListener('load', function (e) {
output.textContent = e.target.result;
});
reader.readAsBinaryString(myFile);
}
});
</script>
</body>
</html>
What techniques are used to load a file (ASCII or Binary) into a variable (var file = "text";) in JavaScript?
You want to use the new HTML5 File API and XMLHttpRequest 2.
You can listen to files being either selected via a file input or drag & dropped to the browser. Let's talk about the input[type="file"] way.
<input type="file">
Let's listen for files being selected.
var input; // let input be our file input
input.onchange = function (e) {
var files = input.files || [];
var file = files[0];
if (file) {
uploadFile(file);
}
};
What you need to create a real multipart file upload request is a FormData object. This object is a representation of the body of your HTTP POST request.
var uploadFile = function (file) {
var data = new FormData();
data.append('filename', file);
// create a HTTP POST request
var xhr = new XMLHttpRequest();
xhr.open('POST', './script.php', true);
xhr.send(data);
xhr.onloadend = function () {
// code to be executed when the upload finishes
};
};
You can also monitor the upload progress.
xhr.upload.onprogress = function (e) {
var percentage = 100 * e.loaded / e.total;
};
Ask if you need any clarification.
If you want to use the new HTML5 way this is how I did it... keep in mind that I made a method called File() and this is not a true HTML5 method its a wrapper to it... this might be changed in the future so beware (maybe rename it).
HTML:
<html>
<body>
<input type="file" id="files" name="file"/>
<button onclick="load()">Load File</button><br /><br />
<div id="content"></div>
<script>
function load() {
var fileObj = document.getElementById("files");
var fp = new File(fileObj);
fp.read(callback);
}
function callback(text) {
var content = document.getElementById("content");
content.innerHTML = text;
}
</script>
</body>
</html>
JavaScript:
function File(name) {
this.name = document.getElementById(name) ? document.getElementById(name).files : name.files ? name.files : name;
}
// Reads the file from the browser
File.prototype.read = function(callback) {
var files = this.name;
if (!files.length) {
alert('Please select a file!?');
return;
}
var file = files[0];
var reader = new FileReader();
reader.onloadend = function(evt) {
if (evt.target.readyState == FileReader.DONE) { // DONE == 2
callback(evt.target.result);
}
};
var data = file.slice(0, file.size);
reader.readAsBinaryString(data);
}
Have the JavaScript being generated inside a PHP or Rails (or whatever you use server-side) and include the file.
<?php
$my_string = file_get_contents('/path/to/file.txt');
?>
<script>
var my_js_file_string = "<?php echo $my_string; ?>";
...
document.write(my_js_file_string);
</script>