@god147
mid(a3,4,1)1代表只取1个字符4代表从第4个字符开始整个意思就是从a3单元格的字符串第4个字符起取1个字符括号的应用是成对使用的,与公式和函数的写法有关=if(mid(a3,4,1)="1","
北京",if(mid(a3,4,1)="2","
上海",if(mid(a3,4,1)="3","深圳")))这个公式也可以写成=vlookup(--mid(a3,4,1),{1,"北京";2,"上海";3,"深圳"},2,)或=choose(mid(a3,4,1),"北京","上海","深圳")。