In C#, how do I know which exceptions to catch?

Question

I\'ve gotten in the habit of using a general catch statement and I handle those exceptions in a general manner. Is this bad practice? If so, how do I know which specific exc

Answer 1

Yes, that is bad practice. Rule of thumb: "catch the exceptions you are in a position to respond to, let the other ones go."

try {
    File.Open(usersChosenFile, FileMode.Open);
} catch(FileNotFoundException) {
    // tell the user the file is gone, give them a chance to respond
    // this is good
} catch(UnauthorizedAccessException) {
    // this is good too
} catch(Exception) {
    // what did you just catch? Who knows. What if its OutOfMemoryException?
    // Do you really want to deal with that here? Let this one go by
}