Opening a pdf file on iOS devices is failed

Hello there,

I am developing an app on both Android and iOS devices (says, iPhone and iPad). Some functions work well on Android devices (where I build them on Windows 7): opening a PDF file and uploading screen shots. Here I mainly ask a solution to open the PDF file on iOS devices.

Here are what I have done and what the code (C#) works well on Android devices:

1. The PDF file 'manual.pdf' is initially put in the 'Resources' folder (in Unity editor).

2. I change the file extension of the PDF file from 'pdf' to 'bytes'

3. When the function to load the PDF file is triggered, I load this file using the code:

   TextAsset manual = Resources.Load("manual", typeof(TextAsset)) as TextAsset;

4. The 'TextAsset manual' is then saved as a PDF file on the devices:

   System.IO.File.WriteAllBytes(Application.persistentDataPath + "/manual.pdf", manual.bytes);

5. I also tried this pieces of codes on iOS devices:

   string path = System.IO.Path.Combine(Application.persistentDataPath, "manual.pdf");

   FileStream fs = new FileStream(path, FileMode.Create);

   BinaryWriter w = new BinaryWriter(fs);

   w.Write(manual.bytes);

   w.Close();

   fs.Close();

6. Then load the PDF file which was just saved onto the devices; I tried these codes:

   Application.OpenURL(path);

   Application.OpenURL("file://"+path);

   Application.OpenURL("file:///"+path);

   ---

The above is what I have done and works well on Android devices, but not works on iOS devices at all (tested on new iPad).

Some questions I would like to ask:

1. Is there any better method to save the PDF file onto the devices when the app is installed?

2. I found that if one wants to open Facebook page using Facebook app, one should call OpenURL with the parameter: "fb://xxx...". Does it have the similar way to open a pdf file?

3. I am wondering if there is something wrong with these codes? The codes work well on Android devices and even on Mac's Unity to test it directly. Maybe I have to do some modifications on Build Settings?

Hopefully some people can provide me suggestions! Thank you.