filereader

I'm trying to create a node app that reads a textfile line by line using the 'readline' module, and prints it to the console. var lineReader = require('readline'); lineReader.createInterface({ input: fs.createReadStream('./testfile') }); lineReader.on('line', function(line){ console.log(line); }); According to the module's documentation, there should be an 'on' method . However when I log the instance of the readline object I created, I don't see an 'on' method anywhere: { createInterface: [Function], Interface: { [Function: Interface] super_: { [Function: EventEmitter] EventEmitter: [Circular

------------恢复内容开始------------ IO流概述 java中用于传输数据的工具。 IO流能干什么：在本地磁盘和网络上操作数据。 IO流的分类： （1）按数据流向分： ①输入流②输出流 （2）按操作方式分： ①字节流 以字节的形式操作数据 InputStream:字节输入流，以字节的形式读取数据。字节输入流的顶层抽象类 OutputStream：字节输出流，以字节的形式写出数据 ②字符流 以字符的形式操作数据 Reader ：字符输入流 Writer：字符输出流 这四个类都是抽象类，在使用时要使用它们的子类 IO流体系：字符流：按字符读写数据的IO流：Reader：FileReader 普通字符输入流 BufferedReader 高效字符输入流 Writer：FileWriter 普通字符输出流 BufferedReader 高效字符输出流 字节流：InputStream：FileInputStream BufferedInputStream OutputStream：FileOutputStream BufferedOutputStream File类 一个File对象代表磁盘上的某个文件或文件夹 构造方法 ： File(String pathname):根据字符串形式的路径来创建其对应的File对象 File(String parent,String

For example, say the user loads some very large images or media files in to your web app. When they return you want your app to show what they've previously loaded, but can't keep the actual file data in LocalStorage because the data is too large. ebidel This is NOT possible with localStorage . Data stored in localStorage needs to be one of the primitive types that can be serializable. This does not include the File object. For example, this will not work as you'd expect: var el = document.createElement('input'); el.type='file'; el.onchange = function(e) { localStorage.file = JSON.stringify

I am looking for a solution that allows me to take a file from a file upload input and preview it by setting the document.body.style.backgroundImage. The following code works to display a preview in an Image element: function setImage(id, target){ input = document.getElementById(id); if (input.files && input.files[0]) { var reader = new FileReader(); reader.onload = function (e) { target.src = e.target.result; }; reader.readAsDataURL(input.files[0]); } } Where id is the id of the <input type='file'> , and target is the <img> element. The following code outlines what I would like to happen,

字符流 只能读写文本文件 Reader 抽象类 字符输出流的父类 Writer 抽象类 字符输出流的父类 字符转换输出流: OutputStreamWriter(OutputStream out)： 创建使用默认字符编码的 OutputStreamWriter OutputStreamWriter(OutputStream out, String charsetName) ： 创建使用指定字符集的 OutputStreamWriter 案例1： public class MyTest { public static void main(String[] args) throws IOException { //输出流，所关联的文件如果不存在则自动创建 OutputStreamWriter out = new OutputStreamWriter(new FileOutputStream("a.txt")); //往文件中写入数据 out.write('你'); //一次写入一个字符 out.write('好'); out.flush(); //字符流要刷新一下 out.write('你'); //一次写入一个字符 out.write('好'); out.write('你'); //一次写入一个字符 out.write('好'); out.flush(); out.write(

I've not been able to resolve the following exception in the code below. What is the problem with the way I use BufferedReader? I'm using BufferedReader inside the main method OUTPUT :- ParseFileName.java:56: unreported exception java.io.FileNotFoundException; must be caught or declared to be thrown BufferedReader buffread = new BufferedReader (new FileReader("file.txt")); // ParseFileName is used to get the file name from a file path // For eg: get - crc.v from "$ROOT/rtl/..path/crc.v" import java.util.regex.Pattern; import java.io.*; public class ParseFileName { //Split along /'s , and

在前一篇文章《 File杂谈——拖拽上传前传 》中我制作了一个 静态的拖拽上传界面 ，拖拽文件到显示区域释放，可以显示拖入文件的基本信息。本文将在此基础上进一步加工，打造一个完整的 拖拽上传示例 。 示例说明 点击区域选择文件或直接将文件拖入区域，触发文件上传功能，文件将异步发送到服务器。待服务端处理完成后返回基本信息，在页面中显示。由于服务器容量问题，本示例未做文件保存处理，只是简单的将文件基本信息返回，文件上传的后端具体处理逻辑需要自行补充。 新的小伙伴FormData 我们知道，传统的文件上传如果要实现异步的效果，我们会使用iframe去模拟，或使用flash上传插件。但是今天，我们又认识了一位新成员——FromData，它可以通过js创建表单对象，并可以向该对象中添加表单数据（字符串、数字、文件等）。再结合我们熟悉的XMLHttpRequest对象，将表单数据异步提交到服务端，这样我们的问题就解决了。 下面，我们来看下核心代码： function uploadFile(fs) { var len = fs.length; for (var i = 0; i < len; i++) { sendFile(fs[i]); } } function sendFile(file) { var xhr = new XMLHttpRequest(), fd = new FormData

Big picture here is that I'm trying to get a photo gallery working for a large number of photos. Currently I'm using the raw URL of the images as gallery thumbnails, which is incredibly slow and crashes older devices quickly. I'd like to create a thumbnail of each photo that is taken with my app's camera and store these either locally or on a backend database. However, I haven't found a good solution. I tried the thumbnailer plugin here but my build failed after installation. I think this only supports Cordova up to 2.9 and I'm using 3.3: https://github.com/maxbasmanov/PhoneGap_Thumbnailer

I have a fixed length file and would like to read its data into class objects. These objects will be further used to insert/update data in Database. Although it can be done with StreamReader, I am looking for a more sophisticated solution. FileHelper is another solution but I do not want to use an open source code in my program. Is there any other option? In the below link, one user has answered this similar question but it is not elaborated: https://codereview.stackexchange.com/questions/27782/how-to-read-fixed-width-data-fields-in-net I tried to implement this but I am unable to find Layout(