excel怎么生成数字和字母混合的乱码，最好是乱码12位数的

=CHOOSE(RANDBETWEEN(1,3),CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)),CHAR(RANDBETWEEN(97,122)))&……&CHOOSE(RANDBETWEEN(1,3),CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)),CHAR(RANDBETWEEN(97,122)))

注释：1、RANDBETWEEN(1,3)表示在1、2、3中随机选择一个数；
2、CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)),CHAR(RANDBETWEEN(97,122))分别表示随机产生1～9，A～Z，a～z中的一个符号；
3、CHOOSE函数表示随机选择1～9，A～Z，a～z中的一个符号作为密码的某一位，该函数一共使用12次，在把12个符号连起来成一个12位密码。

注意：如果嫌函数太长，可以分步进行，例如：
A1=CHAR(RANDBETWEEN(48,57))
B1=CHAR(RANDBETWEEN(65,90))
C1=CHAR(RANDBETWEEN(97,122))
D1=CHOOSE(RANDBETWEEN(1,3),A1,A2,A3)
把A1到D1全选，向下拉成12行
E1=D1&D2&D3&D4&D5&D6&D7&D8&D9&D10&D11&D12
12位的密码存储在E1中
按F9刷新一次，生成一个新的12位密码

EXCEL2007函数公式，F9刷新结果
=IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))&IF(RANDBETWEEN(1,2)=1,CHAR(RANDBETWEEN(48,57)),CHAR(RANDBETWEEN(65,90)))

=INDEX({1;2;3;4.......;x;y;z},(INT(RAND()*36)+1))&.....&INDEX({1;2;3;4.......;x;y;z},(INT(RAND()*36)+1))
大括号里面补齐，分号分隔，&号连接12
完成后F9刷新下就随机产生一个