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How To Check If A File is in Use with C# code

Is there a way to check if a file is in use?

Problem:

If a file is in use it will most likely be in a state of “READ ONLY”. This state or status may break programs or processes that need to access the file and write to it.

 Solution:

protected virtual bool IsFileLocked(FileInfo file)
{
    FileStream stream = null;

    try
    {
        stream = file.Open(FileMode.Open, FileAccess.Read, FileShare.None);
    }
    catch (IOException)
    {
        //the file is unavailable because it is:
        //still being written to
        //or being processed by another thread
        //or does not exist (has already been processed)
        return true;
    }
    finally
    {
        if (stream != null)
            stream.Close();
    }

    //file is not locked
    return false;
}

 

Resources:

 https://stackoverflow.com/questions/876473/is-there-a-way-to-check-if-a-file-is-in-use