I created 2 instances of same project to apply different changes. So when I open project1 and debug class1, everything is smooth, I can have my breakpoints hit all other debugging features. When I open project2 and close project1, I try to do same debugging on class1(some lines of the code is different), I get warning that
"the breakpoint will currently not hit. a copy of class1.cs was found in project1.dal.dll, but the current source code is the different from ther version"
When I close the VS completely and reopen the projects or If I clear the Temporary ASP.NET Files, Problem is getting resolved. But it happens everytime for me. so my questions are;
1) I wonder why does it happen and how can I resolve it without closing VS or clearing cache files?
2) I know the option called "Uncheck Require source files to exactly match the original version".. Is it safe to do it? or is there any side affects or disadvantages
It is impossible to debug your code in that way - you are creating different symbols for each build so when you debug one version, the other is not compatible with the previous one.
To make the long story short - you cannot debug one version of code when symbols from another version are loaded.
More info: Fixing "The breakpoint will not currently be hit. No symbols have been loaded for this document."
EDIT:
Check this link also: What is the "Temporary ASP.NET Files" folder for?