Sample Download : http://code.msdn.microsoft.com/How-to-check-if-a-file-or-2f9357be
This code snippet will show you how to check if a file or folder exists in the local storage in Windows Store apps.
Use the StorageFolder.TryGetItemAsync method to try to get a file or folder by name, without the need to add error-catching logic to your code (like you would if you used StorageFolder.GetItemAsync). If the file or folder can’t be found, TryGetItemAsync will return null and will not raise an exception. Because the method returns null, you can use it to check if the specified file or folder exists.
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