"PHP_CI Rapid Development Electronic Mall Project Video Tutorial" This set of video tutorials does not simply explain various knowledge points of ci, but adopts a project-driven approach to interpret ci. From simple mvc writing, the use of tool classes and auxiliary functions to ci execution process analysis, core class expansion, and flexible project structure planning, all are explained in detail. What's more important is that by developing e-malls, you can also learn database analysis and design, business logic analysis and processing, thereby accumulating project experience for yourself. While learning the CI framework, you can also accumulate project experience, killing two birds with one stone, wouldn't it be great!