Cannot read file using phonegap APi

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http://stackoverflow.com – i create one html page.in that i have create 2 button write and read. whenever i click write button.Directory and File created but when i click read at that time nothing display.. i am using Phonegap Build for build app not eclipse.. the code as below <!DOCTYPE html> <html> <head> <title>FileWriter Example</title> <script type="text/javascript" charset="utf-8" src="cordova-2.7.0.js"></script> <script src="jquery-1.8.2.min.js"></script> <script src="phonegap.js"></script> <script type="text/javascript" (HowTos)