I suddenly encountered this problem, and tried hundreds of solutions online and no one is helpful to me.
And finally I tried one that is useful:
in the tool-option--> debugging ---> general
*un-tick option : "require source files to exactly match to the original version"
Other solutions:
1."recompile/build the project before adding the break-point"
2.clean/rebuild
3.Build --> Configuration Manager ...and check if the project with the code you're trying to debug is checked for the current build configuration.
4...
转载于:https://www.cnblogs.com/ericsun/archive/2012/07/18/2596814.html