I need to read Data from EditText and When click "Write Data" Button, it needs to save the file in External Storage of Device as .txt file, and when i Click the "Read Data" Button, it needs to retrieve the data and bind in TextView.
System.IO is a good starting point
Yes, you can use Java.IO.File to save the Text to External Storage.
And the following thread contains a sample to save file to External Storage, you can check it.https://forums.xamarin.com/discussion/comment/353787/#Comment_353787
For more details
You can check External storage
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