The main difference between these both are the fact that Convert.ToString() can handle NULL and avoid ObjectReferenceNullException, while .ToString() would break in such case.
It is always good to use the Convert object than the ToString()
Let’s have a look into the Convert.ToString() method. Using a reflector, i got hold of the Convert object below:
public static string ToString(object value, IFormatProvider provider)
IConvertible convertible = value as IConvertible
if(convertible != null)
if(value != null)
Well I guess this would clear up the reason for using the Convert object in you type conversion operations.