Read/Write files from SD Card – PhoneGap/HTML/Javascript

Javascript functions to list out the files in SD card and show it in html div tag
 
Read files
 function BrowseFile()
{

window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function(fs) {

var directoryReader = fs.root.createReader();

directoryReader.readEntries(function(entries) {

var i;

document.getElementById('dirList').innerhtml='';

var child="";

for (i=0; i<entries.length; i++) {

child=child+"<div>"+entries[i].toURI()+"</div>";

alert(entries[i].toURI());

}

document.getElementById('dirList').innerHTML = child;

}, function (error) {

alert(error.code);

})

}, function (error) {

alert(error.code);

});

} 
 
Create a file and write to it
function writeFile()

{

// root file system entry

var root = getFileSystemRoot();

// writes a file

write_file = function(writer)

{

var lineCount = 1;

// set the callbacks

writer.onwritestart = onFileEvent;

writer.onprogress = onFileEvent;

writer.onwrite = onFileWrite;

writer.onabort = onFileEvent;

writer.onerror = onFileError;

writer.onwriteend = function(event)

{

onFileEvent(event);

lineCount += 1;

if (lineCount <= 3)

{

// append a new line

writer.write('Line ' + lineCount + '.\r\n');

}

else {

alert(writer.fileName + ' length=' + writer.length + ', position=' + writer.position);

}

}

// append

writer.seek(writer.length);

// write to file

writer.write('Line ' + lineCount + '.\r\n');

},

// creates a FileWriter object

create_writer = function(fileEntry)

{

fileEntry.createWriter(write_file, onFileSystemError);

};

// create a file and write to it

root.getFile('bbgap2.txt', {create: true}, create_writer, onFileSystemError);

}

Reference links -
http://geekyfry.com/tech-it/smartphones/phonegap/reading-writing-files-from-sd-card-phonegaphtml5javascript/