problem about filereader-Collection of common programming errors


  • Chathuranga Chandrasekara
    javascript html5 file-upload filereader data-url
    I am using the new FileReader API to preview images before upload. This is done using DataURLs. But DataURLs can be massive if the images are large. This is especially a problem for me as the user may upload multiple images at a time and previewing the bunch has actually slowed my browser considerably and actually crashed chrome a few times.Is there any alternative to using DataURLs for previewing images on the client before upload?

  • Sylnois
    php jquery upload blob filereader
    I need your help. I want to create a upload script with HTML, JQuery and PHP. Is it possible to write a script, that can upload very large files(> 5 GB)?I’ve try it with FileReader, FormData and Blobs, but even with these, i can’t upload large files(my browser crashes after selecting a large file).PS: I rly want to write it on myself. Don’t post any finished scripts.Regards

  • Joe
    html5 google-chrome filereader
    I’m trying to read large file (3GB) as slice as 100Mb. ***function sliceMe() {var file = document.getElementById(‘files’).files[0],fr = new FileReader;var chunkSize = document.getElementById(‘txtSize’).value;chunkSize =1048576; var chunks = Math.ceil(file.size / chunkSize);var chunk = 0;document.getElementById(‘byte_range’).innerHTML = “”;function loadNext() {var start, end,blobSlice = File.prototype.mozSlice || File.prototype.webkitSlice;start = chunk * chunkSize;if (start > file.

  • jgille07
    jquery html5 loops filesystems filereader
    I have a code that gets a user’s local directory and then opens a filereader object for each mp3 file it finds in the directory. Sometimes this can be over 1,000 files. How would I optimize this code so that it does not crash the browser? It works perfectly for directories with up to 200-300 files in it, but crashes the browser without any errors in the console log. Any suggestions would be greatly appreciated. Here is the link to a jsFiddle page of my code: http://jsfiddle.net/X6BZe/The fi

  • Robert
    android phonegap filereader cordova
    I’m experiencing an intermittent crash in my Android application running on a Droid X 2.3.4, using Cordova 1.6.1. I’ve created a sample project (http://bit.ly/IWxTv7) that clearly demonstrates the error on the device, but only intermittently. It’s happening frequently enough that if you run the sample and repeat picking a photo, after about 6 attempts you should see the crash. Also note that this functions correctly on iOS and other Android devices, so the fact that it’s intermittent and device/

  • Journeyman
    html5 google-chrome filereader
    I am using the HTML5 FileReader to read a local file. I then want to immediately display the file contents within the browser, prior to uploading to the server.I read the file, and attempt to display it, as follows:var reader = new FileReader();reader.onloadend = function () {_moleculefilestream = reader.result;_molecule.filename = filelist[0].name;var filetype = _molecule.filename.substring(_molecule.filename.length – 3);var html = ”;if (filetype == ‘jpg’ || filetype == ‘gif’ || filetype == ‘

  • user675803
    javascript filereader
    I am trying to implement a file upload with dnd and FileReader for image preview. It works quite good and also if i upload multiple files at ones. But when i upload a second time images > ~1,6MB it crashes in chrome (firefox runs fine). probably a bug in chrome but maybe anyone knows how to solve this? Here an example: http://jsfiddle.net/PTssx/7/

  • Hassan Habbak
    android crash phonegap filereader
    I am facing a problem in what should have been a simple task of capturing video inside phonegap app. What I am trying to do is to start video recorder, capture a video file, get back the mediaFile and then extract the file path from it and read it using fileReader. I need the file to be in binary base64 so I am using readAsDataURL to read it.What happens though is as follow. The video is captured correctly, the file path is read correctly. Filereader gets initiated. Then the app crash without th

  • Mario Hébert
    google-chrome firefox crash filereader
    We try to upload a zip file using the “FileReader” javascript object on the client. For small files, everything seems to be fine. If we use a zip input file of 132Mo, in Firefox v21.0 on Windows 7, the first upload from the local disk thru the javascript object works well. But, if we try to select another file and start the transfert, Firefox crashes.. In Chrome v27.0 on Windows 7, it crashes(see the ‘oups’ page) on the first try. We tried on a Mac OS with same browsers without problem. Mainly s

  • user2002076
    javascript html5 filereader
    I am reading in files inside of a web worker. However, when I try to read the file I keep getting this error: Uncaught DataCloneError: An object could not be cloned. The only line of code that throws this error is the reader.readAsText(file). Can anyone explain why this is happening?self.requestFileSystemSync = self.webkitRequestFileSystemSync || self.requestFileSystemSync;try{var fs = requestFileSystemSync(TEMPORARY, 1024 * 1024); } catch (error) {onError(error);}self.addEventListener(‘message’

  • Okarin
    javascript html5 filereader
    I’ve been using the FileReader API to read local files and feed them to a Java applet, and this has worked for now. The file gets read, the applet behaves like it’s supposed to. The function which passes the contents of the file (as String) to the applet is currently called INSIDE the function assigned to the onloadend() event of the Reader (I use onloadend() insteat than onload() for some error handling needs. Though maybe I could replace that with a try/catch instruction, I’ll look into it). N

  • bart2puck
    php jquery ajax filereader
    I have a script that takes an uploaded csv, and passes the data to a php script via ajax for field validation. this works perfect. the php responds with a result, and shows it on the page. lets say the php script comes back and says “you need to change field X”, the user would then update his csv and click the add file button again in an attempt to retry. this 2nd attempt fails. the add files button brings up browse window, but page never shows new csv data. any idea?<script>$(‘#the

  • Dozent
    jquery json phonegap filereader
    I’ve implemented code for loading json data from external file on device. The program should work like this: On click event first it will try to look into local storage file (course.txt) and if it’s exist read and display it (list of titles).HTML code:<div data-role=”page” id=”page1″><a href=”#page2″ onclick=”courseList()”>Load Course</a></div> </div> <div data-role=”page” id=”page2″><p id=”text” align=”center”></p><div id=”print”></div>

  • Anto
    javascript api firefox filereader
    The FileReader API is used in my application to read the uploaded file(s) as ‘Binary Strings’. My application acts as a middleware. When used with one back-end, it worked as expected, but with the other back-end, it did not work. The browser I’m using is Firefox 16. The sample code is as follows,if(data[i]!=”” && data[i]!=undefined){var readDat = new FileReader();readDat.onloadend = function(dFile,ind){return function(evnt){data[ind] = evnt.target.result;if((evnt.target.readyState == 2)

  • QuakeDK
    javascript html5 filereader
    I have a problem with my little project. Every time the music player is loading new songs into playlist or you are pressing a song on the list to get it playing, it’s using a lot of memory, and it stays high until you shut it down. I think its every time I’m using the filereader API that it uses memory, but I’m also loading ID3 information with the jDataView.js script which I also think is taking a lot of memory.Do you guys have any suggestion, to load,store and play songs with the FileReader, w

  • user2127833
    javascript jquery api file filereader
    When the user selects photos, a text input with a title label is put next to the preview photo. But when the user submits multiple files, the inputs have the same name thus not working correctly. function showPreview(e) {var $input = $(this); var inputFiles = this.files;for (var i = 0, f; f = inputFiles[i]; i++) {if(inputFiles == undefined || inputFiles.length == 0) return;var inputFile = inputFiles[i];var reader = new FileReader();reader.onload = function(event) {$(“<div class=’preview’>&

  • user2117386
    html5 filereader
    Here the problem in below code is that when i want to show thumbnails for 40 large images . the firefox in windows is crashing as the cpu usage increases while loading one image after other.i know its because loading the image of full size (around 9000 Kb).is there any way just to show thumbnail rather than loading full size in html5…dropbox.addEventListener(“drop”, dropUpload, false);function dropUpload(event) {noop(event); var dropMethod = event.dataTransfer;var classicMethod = event.target

  • beerbajay
    python ascii binary-data filereader non-ascii-chars
    I’m using python to read a text file with the segment below(can’t post a screenshot since i’m a noob) but this is what is looks like in notepad++:NULSOHSOHNULNULNULSUBMesssage-ID:error:Traceback (most recent call last):File “<pyshell#3>”, line 1, in <module>print(f.readline())File “C:\Python32\lib\encodings\cp1252.py”, line 23, in decodereturn codecs.charmap_decode(input,self.errors,decoding_table)[0] UnicodeDecodeError: ‘charmap’ codec can’t decode byte 0x8f in position 7673: charac

  • ronmrdechai
    javascript filereader
    I’m using a FileReader and the HTML file dialog to read a file in my script. How do I pass this file’s contents out of the FileReader.onload function?function readFileData(evt) {var file = evt.target.files[0];var reader = new FileReader();reader.onload = function(e) {var contents = e.target.result;}reader.readAsText(file); } document.getElementById(‘file’).addEventListener(‘change’, readFileData, false);/* I want to access the contents here */I tried sticking returns in the readFileData and onlo

  • user1876508
    html5 file angularjs filereader
    I am trying to save the text from a file into a string inside the rootscope. What I have so far is a directive, which loads properly, and a function which checks the rootfunction callData($rootScope) {console.log(“function working”);console.log($rootScope.data); }angular.module(‘spreadsheetApp’).directive(‘fileReader’, function($rootScope) {return {restrict: ‘E’,scope: true,templateUrl:’views/fileReaderTemplate.html’,controller: ‘fileReaderController’,link: function (scope, element, attributes,

  • Emma
    javascript safari filereader
    (Am new to web programming, so apologies for any lack of rudimentary knowledge.)My page allows a user to select a file that is then read clientside & displayed in a textbox on the page. The easiest way I found to do this was to use a FileReader object, which works fine in Firefox and Chrome.This doesn’t work in Safari (yet), so what should I do instead?//When the eventlistener detects a change in the input file… var file = evt.target.files[0] var reader = new FileReader(); reader.onload =

  • TK123
    javascript jquery html5 filereader
    I found a javascript that deals with HTML5 File Reader API. It’s written in pure javascript, I am in the process of converting it to a jQuery script. But am getting stuck at this point.This works:document.getElementById(‘drop-area’).addEventListener(‘drop’, function(e) {e.preventDefault();e.stopPropagation();console.log(e.dataTransfer.files); // outputs the right stuff }, false);This fails:$(‘#drop-area’).on(‘drop’, function(e) {e.preventDefault();e.stopPropagation();console.log(e.dataTransfer.f

  • Rudie
    javascript file html5 filereader
    With the new File API in Javascript you can read files in Javascript to create dataURLs to show clientside pictures clientside. I’m wondering if you can reach the File object within the FileReader’s onload callback. I will illustrate this with an example:var div = document.createElement(‘div’); div.ondrop = function(e) {e.preventDefault();e.stopPropagation();var files = e.dataTransfer.files;for ( var i=0; i<files.length; i++ ) {var file = files[i]; // this is the file I want!!var filereader =

  • Drew LeSueur
    html5 google-chrome filereader
    Can someone give me an example of using the FileReader API go get contents of a file in chrome?It seems to be returning undefined for me.<!doctype html> <html> <script> function handle_files(files) {console.log(files)reader = new FileReader()ret = []for (i = 0; i < files.length; i++) {file = files[i]console.log(file)text = reader.readAsText(file) //readAsdataURLconsole.log(text) //undefinedret.push(text)}console.log(ret) // [undefined]} </script> <body> FileReade

  • barry
    javascript safari filereader referenceerror
    I’m aware of the fact that the FileReader Object is not available in Safari 5.0.5. I have a script that uses it and thought that i’d just be able to detect whether the object exists to run some alternate code, as is suggested here,http://www.quirksmode.org/js/support.htmlSo my code is,if( FileReader ) {//do this}else{//the browser doesn’t support the FileReader Object, so do this }The problem is, i’ve tested it in Safari and once it hits the if statement i get this error and the script stops run

  • Mikko Ohtamaa
    javascript file-upload filereader
    I’m trying to change file upload image to select or click on image on the same page in this canvas related script.function aFileIsLoaded(e1) {var filename = e1.target.files[0];var fr = new FileReader(); fr.onload = function(e2) {backgroundimage = new Image();backgroundimage.src=e2.target.result;var context = document.getElementById(‘myCanvas’).getContext(‘2d’);context.canvas.width = backgroundimage.width;context.canvas.height = backgroundimage.height;context.drawImage(backgroundimage, 0, 0, back

  • Hooked
    javascript html5 filereader fileapi
    I use Chrome 12 on Mac OS X and I’ve included jQuery 1.6.1 within the document.I try to read the contents of a file as text and save it in a data-object with the following function:this.upload = function(file) {console.log(‘FileHandler.upload called with ‘ + file.name + ‘.’);console.log(file);console.log(this.reader);data = {content: this.reader.readAsText(file)}console.log(‘Content: ‘ + data.content); }”file” seams to be a valid file-object and “this.reader” is a fresh instance of type FileRead

  • ovangle
    javascript filereader
    I couldn’t find an answer to this problem I’ve been having. function UploadBar() {this.reader = new FileReader();this.reader.addEventListener(“onloadstart”, function(evt) {alert(“Hello World”);}, false); }when I try to run this code it gives me an undefined_method_error in the javascript debugger in chrome. Could anyone be so kind as to tell me what is wrong here?

  • Andrew Whitaker
    javascript filereader
    I wish to read the contents of an upload file into a Javascript variable.The program used to work using file.getAsBinary but this is now depricated and needs to be updated to use FileReader()A form has a file upload selection an onsubmit runs a function uploadDB() in a javascript.The variable dbname is passed okay as is the file name from the upload selection I can see it with an alert or console.log.The final bfile variable to receive the file text is undefined. I have tried both readAsText an

  • StackP
    java input io output filereader
    I’m trying to do this assignment:Write a program that reads a file and writes a copy of the file to another file with line numbers inserted.So far, I have written this much of the code:import java.io.*; import java.util.Scanner;public class Question43 { public static void main(String[] args) throws IOException {Scanner fileIn = new Scanner(new File(“Assign4.txt”) );FileWriter fileOut = new FileWriter(“FileOut.txt”);PrintWriter output = new PrintWriter(fileOut);String []array = new String[10];in