Let\'s say I have an integer that I need to convert to a string (I might be displaying the value to the user by means of a TextBox, for example.
Should I prefer
With its large number of overloads, Convert.ToString() is useful as a catch-all for all sorts of input types, handy when you are dealing with a potential range of types. If you know that your input is definitely an "int", I would use the ToString() method on it directly (that's what Convert.ToString() is going to be calling by proxy anyways.)
One test is
//This will set the variable test to null:
string test = Convert.ToString(ConfigurationSettings.AppSettings["Missing.Value"]);
//This will throw an exception:
string test = ConfigurationSettings.AppSettings["Missing.Value"].ToString();
Got the above ready example from http://weblogs.asp.net/jgalloway/archive/2003/11/06/36308.aspx
You can find some benchmarks between the two at http://blogs.msdn.com/brada/archive/2005/03/10/392332.aspx
So, it depends what you prefer and what your style is.