解决办法:设置精度
QString::number(2285764.2,'f',1) ;
参考:https://blog.csdn.net/xiaobai_2511/article/details/51832885?depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromBaidu-1&utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromBaidu-1