Question

I’ve got a small piece of code that is parsing an index value to determine a cell input into Excel. It’s got me thinking…

What’s the difference between

xlsSheet.Write('C' + rowIndex.ToString(), null, title); 

and

xlsSheet.Write(string.Format('C{0}', rowIndex), null, title); 

Is one ‘better’ than the other? And why?

Answer 1

Before C# 6

To be honest, I think the first version is simpler – although I’d simplify it to:

xlsSheet.Write('C' + rowIndex, null, title); 

I suspect other answers may talk about the performance hit, but to be honest it’ll be minimal if present at all – and this concatenation version doesn’t need to parse the format string.

Format strings are great for purposes of localisation etc, but in a case like this concatenation is simpler and works just as well.

With C# 6

String interpolation makes a lot of things simpler to read in C# 6. In this case, your second code becomes:

xlsSheet.Write($'C{rowIndex}', null, title); 

which is probably the best option, IMO.