I made one project depend on another , but ...

[huzhongshan]

I use project->properties->building settings->project dependencies to make a project depend on b project.

when I made some changes in b project source files , I choose build a project the b project will not be build.

Does IDE check the dependencies changes when build the main project? if yes , hot to set this property in menu?

[oBFusCATed]

You have to setup an external dependency.

Project A should depend on the output (probably dll) of Project B.

You have to go to Project -> Properties -> Build options -> Dependencies -> External deps -> add the path to the file generated by project b

[huzhongshan]

 when I change source code in project b  and build the project a , can the project b  be build automatically?

[oBFusCATed]

Yes, it will, if you setup it correctly