Also, you should know, this is an "all or nothing" situation. You can not have one page that runs without Debugging and one pages the does in the same assembly.
Also, ONLY use debugging in a development environment as it requires far more overhead from the server and can cause preformance problems in general. Always move applications to a production server with debugging turned off.
Read this if you want to know how to get a correct reply for your question:
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