The AppendToLog method adds a string to the end of the Web server log entry for this request. You can call it multiple times in one section of script. Each time the method is called it appends the specified string to the existing entry.
Response.AppendToLog string
string
The text to append to the log file. Because fields in the Internet Information Server log are comma-delimited, this string cannot contain any comma characters (,). The maximum length of this string is 80 characters.