Later, Zhang Xu watched the graceful dance of Gong Sundaniang Xihe Jianfa in Yexian, and realized the vivid charm of calligraphy, which was smooth, marching and rhythmic. Since then, his cursive script has made great progress. During the reign of Emperor Xuanzong of the Tang Dynasty in Kaiyuan and Tianbao, Zhang Xu was appointed as the official position of Jingzhao (Xi 'an), who was in charge of government affairs. Therefore, people call him "Zhang Changshi".