Utils

<script type="text/javascript">

 var fileName = "local:///data/fooFile.txt";

 function handleOpenedFile(fullPath, blobData) // callback function that is passed when using the blackberry.io.file.readFile API
 {
   xmlString = blackberry.utils.blobToString(blobData); 
 }

 try{
     if (blackberry.io.file.exists(fileName)) {
		    blackberry.io.file.readFile(fileName, handleOpenedFile);
     } 
 }
 catch (ex) {
     alert("exist: " + ex.toString(0));
 }

</script>

<script type="text/javascript">

var myID = blackberry.utils.generateUniqueId();

</script>

<script type="text/javascript">
var myURL = "https://bdsc.webapps.blackberry.com/html5/";

var URLObj = blackberry.utils.URL(myURL); 

</script>

<script type="text/javascript">

var myBlob = blackberry.utils.stringToBlob ("This is some sort of string that I would like to encode", "UTF-8");
var filePath, fileDir;

// Check what device you are using
var OSversion = blackberry.system.softwareVersion; // Note: On the Playbook, only the OS Version will actually say the what type of device it is. For handheld device, blackberry.system.model will return the actual model (ie. 9780)

// Establishing where to save my file depending on which device I have
if (OSversion.indexOf("Playbook") == -1) { // Device is BlackBerry
    
   //Now need to check if there is a SD card on the device
   if (blackberry.io.dir.exists("file:///SDCard")) { //The only way to see if the SDCard is inserted into the device is by checking to see if the directory is there.

         fileDir = "file:///SDCard/dir1";
         blackberry.io.dir.createNewDir(fileDir);

   } else { // Apparently there no SD card, so we're saving the blob on the local device

         fileDir = "file:///store/dir1";
         blackberry.io.dir.createNewDir(fileDir);

   }
} else {
   // Device is Playbook

   // To make this example easier, I did not turn on "File Sharing" and choosing to save in the app storage area.	 
   fileDir = blackberry.io.dir.appDirs.app.storage.path + "/dir1";  
                                                   
   blackberry.io.dir.createNewDir(fileDir);
}

try {
   blackberry.io.file.saveFile(filedir + "/blob.txt", myBlob);
} catch (e) {
   alert('e.message = ' + e.message);
}			

</script>