With classic ASP, string formatting and concatenation can be more than a pain. Line after line of 'strSQL = strSQL & "more text"' can be painful and very problematic. With ASP.Net and C# however, I've recently discovered the beauty of string.Format(), and just how easy it is to build strings with it.

With old-school ASP, you may have some code like this:

strSQL = "SELECT FROM articles WHERE topic = '" & strTopic & "'"

if strAuthor <> "" then
     strSQL = strSQL & " AND author = '" & strAuthor & "'"
end if

OK, that's easy enough. But when you're querying or inserting with many parameters/values, things can get messy. So with C#, you can do the same with slightly neater code:

string strSQL = "SELECT FROM articles WHERE topic = '" + strTopic + "'";

if (strAuthor != "")
     strSQL += " AND author = '" + strAuthor + "'";

BUT, with string.Format() you can create very efficient easy code:

string condAuthor = (strAuthor != "" ? "" : " AND author = '" + strAuthor + "'");
string strSQL = string.Format("SELECT FROM articles WHERE topic = '{0}'{1}", strTopic, condAuthor);

Using string formatting, you can place as many {#} arguments in the text as you want, and specify them afterwards. C# automatically insterts them into the text. Very clean.