filereader

I have long file I need to parse. Because it's very long I need to do it chunk by chunk. I tried this: function parseFile(file){ var chunkSize = 2000; var fileSize = (file.size - 1); var foo = function(e){ console.log(e.target.result); }; for(var i =0; i < fileSize; i += chunkSize) { (function( fil, start ) { var reader = new FileReader(); var blob = fil.slice(start, chunkSize + 1); reader.onload = foo; reader.readAsText(blob); })( file, i ); } } After running it I see only the first chunk in the console. If I change 'console.log' to jquery append to some div I see only first chunk in that div

Trying to use fileReader.readAsBinaryString to upload a PNG file to the server via AJAX, stripped down code (fileObject is the object containing info on my file); var fileReader = new FileReader(); fileReader.onload = function(e) { var xmlHttpRequest = new XMLHttpRequest(); //Some AJAX-y stuff - callbacks, handlers etc. xmlHttpRequest.open("POST", '/pushfile', true); var dashes = '--'; var boundary = 'aperturephotoupload'; var crlf = "\r\n"; //Post with the correct MIME type (If the OS can identify one) if ( fileObject.type == '' ){ filetype = 'application/octet-stream'; } else { filetype =

一、fileReader 用于读取文件 FileReader 方法： abort() 终止读取 readAsBinaryString(file) 将文件读取为二进制编码 readAsDataURL(file) 将文件读取为DataURL编码 readAsText(file, [encoding]) 将文件读取为文本 readAsArrayBuffer(file)​​​​​​​ 将文件读取为arraybuffer 通过不同的方式读取文件 来源： https://www.cnblogs.com/tianya-guoke/p/11333113.html

I would like to know the specific difference between BufferedReader and FileReader . I do know that BufferedReader is much more efficient as opposed to FileReader , but can someone please explain why (specifically and in detail)? Thanks. In simple manner: A FileReader class is a general tool to read in characters from a File. The BufferedReader class can wrap around Readers, like FileReader, to buffer the input and improve efficiency. So you wouldn't use one over the other, but both at the same time by passing the FileReader object to the BufferedReader constructor. Very Detail FileReader is

My file reader api code has been working good so far until one day I got a 280MB txt file from one of my client. Page just crashes straight up in Chrome and in Firefox nothing happens. // create new reader object var fileReader = new FileReader(); // read the file as text fileReader.readAsText( $files[i] ); fileReader.onload = function(e) { // read all the information about the file // do sanity checks here etc... $timeout( function() { // var fileContent = e.target.result; // get the first line var firstLine = e.target.result.slice(0, e.target.result.indexOf("\n") ); }} What I am trying to do

What is the difference between Reader and InputStream? And when to use what? If I can use Reader for reading characters why I will use inputstream, I guess to read objects? Berin Loritsch An InputStream is the raw method of getting information from a resource. It grabs the data byte by byte without performing any kind of translation. If you are reading image data, or any binary file, this is the stream to use. A Reader is designed for character streams. If the information you are reading is all text, then the Reader will take care of the character decoding for you and give you unicode