How to select a Chinese verification code

How to select a Chinese verification code? The English verification code uses an array of random subscript defining 26 uppercase/lowercase letters and numbers to obtain a random verification code & nbsp; how can I obtain a random Chinese character for the Chinese verification code? Will an array of Chinese characters defined in the same way as in English be too large ?, Notice the Chinese character UCS-2 code from 0x4e00 to 0x9fa Chinese verification code how to choose?
The English verification code uses an array of random subscript defining 26 uppercase/lowercase letters and numbers to obtain a random verification code.
How can I obtain random Chinese characters for the Chinese verification code? Will an array of Chinese characters defined in the same way as in English be too large?

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Note that the UCS-2 encoding of Chinese characters from 0x4e00 to 0x9fa6 is continuous
So you only need
$ Ch = iconv ('ucos-2', 'utf-8', pack ('N', rand (0x4e00, 0x9fa6 )));
You can obtain a random Chinese character.


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Create a common font and the verification function does not need to list all common words