XMLHttpRequest 2.0 methods for interfacing with FileReader

Yes:

Domstring, Document, FormData, Blob, File, ArrayBuffer

Look at Zhang's blog. http://www.zhangxinxu.com/wordpress/2013/10/understand-domstring-document-formdata-blob-file-arraybuffer/

Where the FileReader interface does some preparation:

1, the method of FileReader interface

The FileReader interface has 4 methods, 3 of which are used to read the file and the other to interrupt the read. The method does not return a read result, regardless of the success or failure of the read, which is stored in the result property.

Method of FileReader interface

Method Name	Parameters	Description
Readasbinarystring	File	To read a file as a binary encoding
Readastext	File,[encoding]	To read a file as text
Readasdataurl	File	Read the file as Dataurl
Abort	(none)	Terminal Read operations

2. FileReader Interface Event

The FileReader interface contains a complete set of event models for capturing the state when a file is read.

Events for the FileReader interface

Event	Describe
Onabort	Interrupt
OnError	Error
Onloadstart	Begin
OnProgress	is reading
OnLoad	Successfully read
Onloadend	Read complete regardless of successful failure

varUppreviewimg =function (options) { This. Uppreview (Options)} Uppreviewimg.prototype={isie:function () {//whether it is IE        return!!window.    ActiveXObject; }, Isie6:function () {//whether it is IE6        returnIsie () &&!window.    XMLHttpRequest; }, Isie7:function () {//whether it is IE7        returnIsie () &&!isie6 () &&!isIE8 ()}, Isie8:function () {returnIsie () &&!!Document.documentmode; }, Setcss:function (_this,cssoption) {if(!_this| | _this.nodetype = = =3|| _this.nodetype = = =8|| !_this.style) {            return; }         for(varCsinchcssoption) {_this.style[cs]=Cssoption[cs]; }        return_this; }, Uppreview:function (options) {var_e =OPTIONS.E, Preloadimg=NULL; _e.onchange=function () {var_v = This. Value, _body=document.body; Picreg= /(. Jpeg|. Jpeg|. Jpg|. Jpg|. Gif|. Gif|. bmp|. bmp|. Png|. PNG) {1}/; if(!picreg.test (_V)) {Alert ("Please select the correct picture format"); return false; }        if(typeofFileReader = ='undefined') {            if( This. File) {                var_img = Document.createelement ("img"); _img.setattribute ("src", This. file.files[0].getasdataurl ());            Options.preview.appendChild (_IMG); }            Else if( This. IsIE6 ()) {                var_img = Document.createelement ("img"); _img.setattribute ("src", _v);            Options.preview.appendChild (_IMG); }            Else{_v= _v.replace (/[('"%]/g,function (str) {                    returnEscape (Escape (str));                });  This. SETCSS (options.preview,{"Filter":"Progid:DXImageTransform.Microsoft.AlphaImageLoader (enabled= ' true ', sizingmethod= ' scale ', src=\ '"+_v+"\ ')","Display":"Block"                }); }        }        Else{            varReader =NewFileReader (), _file= This. files[0]; Reader.onload=(function (file) {returnfunction () {var_img = Document.createelement ("img"); _img.setattribute ("src", This. Result);                Options.preview.appendChild (_IMG);            };            }) (_file); Reader.onerror=function () {alert ("file read Data error");        } reader.readasdataurl (_file); }}}}module.exports= Uppreviewimg;

*
* e-long passing pictures
* Preview of the Div displayed
* @param options
* * A plugin that uploads images immediately

XMLHttpRequest 2.0 methods for interfacing with FileReader