E-assessment learning, which combines the advantages of e-assessment and learning, was proposed in educational settings. However, it still makes most of learners feel anxious. Thus, this study develops a Joyful Assessment-based Learning System (JALS), which incorporates game-based learning into e-assessment learning. In order to get a complete understanding of how individual differences affect learners' reactions, an empirical study was conducted. Among various individual differences, cognitive styles and prior knowledge were considered as targets to investigate learners' reactions to the JALS. Our results suggest that FD learners preferred to use the game-based learning tool and demonstrated good performance. Conversely, the different level of prior knowledge may affect FI learners' learning preferences and learning performance.