program that opens a local file c datadirectory data txt

Write a program that opens a local file C:DataDirectorydata.txt reads in the data into your program without removing the data from the file and appends new data onto the end of the existing data in the program, and then appends the new data onto the existing data within the file.
For example, if the data file originally contained the following data:

Hello

Then when your program is done, it should say:

HelloHello my name is Bob

Also, you must utilize exception handing technique to validate that the file has been open, and offer the user a chance to enter a correct filename until the file is found.

Hint: Use the overloaded open functions, or use random access methodology.