标题：excel 随机生成大小写字符和数字混合
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时间：2012/4/16 19:24:34
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内容：
=CHAR(RANDBETWEEN(65,90))&CHAR(RANDBETWEEN(97,122))&CHAR(RANDBETWEEN(97,122))&CHAR(RANDBETWEEN(97,122))&CHAR(RANDBETWEEN(97,122))&CHAR(RANDBETWEEN(97,122))
利用char（）函数生成asic码值 利用randbetween（）生成2数字之间的数字
| 字符范围 | 字符集数量 | ASC码起始值 | ASC码结束值 | ASC表示方式 |
| 0-9 | 10 | 48 | 57 | char（randbetween(48,57)） |
| A-Z | 25 | 65 | 90 | char（randbetween(65,90)） |
| a-z | 25 | 97 | 122 | char（randbetween(97,122)） |
| 字符范围 | ASC表示方式 |
| 0-9 | =char（randbetween(48,57)） |
| A-Z | =char（randbetween(65,90)） |
| a-z | =char（randbetween(97,122)） |
这样我们需要随机生成的就是3个字符集这样我们再加一个随机函数让它在1和3里面选 选到1 就选字符集一
if( randbetween(0,1),数字，（if(randbetween(0,1),小写字符，大写字符）
首先我们生成a或者b两种字符串
=IF(RANDBETWEEN(0,1),"a","b")
然后在b上门用这个生成a和b嵌套下 就变生成a或者b或者c了
=IF(RANDBETWEEN(0,1),"a",IF(RANDBETWEEN(0,1),"b","c"))
=IF(RANDBETWEEN(0,1),CHAR(RANDBETWEEN(48,57)),IF(RANDBETWEEN(0,1),CHAR(RANDBETWEEN(65,90)),CHAR(RANDBETWEEN(97,122))))
这样做2个判断就可以了