Question

In .Net you can read a string value into another data type using either <datatype>.parse or Convert.To<DataType>.

I’m not familiar with the fundamentals of parse versus convert so I am always at a loss when asked which one is better/faster/more appropriate.

So – which way is best in what type of circumstances?

Answer 1

The Convert.ToXXX() methods are for objects that might be of the correct or similar type, while .Parse() and .TryParse() are specifically for strings:

//o is actually a boxed int object o = 12345;  //unboxes it int castVal = (int) 12345;  //o is a boxed enum object o = MyEnum.ValueA;  //this will get the underlying int of ValueA int convVal = Convert.ToInt32( o );  //now we have a string string s = '12345';  //this will throw an exception if s can't be parsed int parseVal = int.Parse( s );  //alternatively: int tryVal; if( int.TryParse( s, out tryVal ) ) {     //do something with tryVal  } 

If you compile with optimisation flags TryParse is very quick – it’s the best way to get a number from a string. However if you have an object that might be an int or might be a string Convert.ToInt32 is quicker.