What is the proper way to re-throw an exception in C#? [duplicate]

Answer 1

If you throw an exception without a variable (the second example) the StackTrace will include the original method that threw the exception.

In the first example the StackTrace will be changed to reflect the current method.

Example:

static string ReadAFile(string fileName) {
    string result = string.Empty;
    try {
        result = File.ReadAllLines(fileName);
    } catch(Exception ex) {
        throw ex; // This will show ReadAFile in the StackTrace
        throw;    // This will show ReadAllLines in the StackTrace
    }