Handling VBScript errors when calling script using Ajax - ajax

Question

I have a page that calls a classic ASP/VB script using the jQuery Ajax function, which allows handlers to be specified for success and error results. Those handlers receive back the response from the ASP script, which just executes some SQL code to insert a record into a database. If there's an SQL error that indicates a duplicate key violation, I want to replace the generated error message with a friendly one, using the code below. As I've discovered, that doesn't work because the code never reaches the "if conn.Errors.Count" line. If the SQL generates an error, the code immediately returns with the error message, which includes the line number of the "conn.Execute" line. Is there a way to get this to do what I want?
set conn=CreateObject("ADODB.Connection")
conn.Open ConnString
conn.Execute "INSERT ... " (long statement omitted for readability)
if conn.Errors.Count> 0 then
if instr(conn.Errors(0).Description, "duplicate key") > 0 then
Response.Write "Unable to add herb - code already exists"
else
Response.Write conn.Errors(0).Description
end if
else ' success
Response.Write "Herb added"
end if
conn.Close
set conn=nothing

Answer 1

as others have pointed out, the best solution is to use "on error resume next". so your code would look something like:
on error resume next
set conn=CreateObject("ADODB.Connection")
conn.Open ConnString
conn.Execute "INSERT ... " (long statement omitted for readability)
if Err.Number > 0 then
if instr(Err.Description, "duplicate key") > 0 then
Response.Write "Unable to add herb - code already exists"
else
Response.Write conn.Errors(0).Description
end if
else ' success
Response.Write "Herb added"
end if
conn.Close
set conn=nothing
on error goto 0 '-- this will remove error handling for the rest of the page and can be considered optional in this case