积水20cm使用lua语言转成gb2312模式

"积水20cm" 这个字符串是UTF-8编码的，如果您想将其转换为GB2312编码，可以使用以下代码：

-- UTF-8到GB2312编码转换函数
function utf8ToGb2312(utf8Text)
    local gb2312Text = ""
    for i = 1, #utf8Text do
        local curByte = string.byte(utf8Text, i)
        local byteCount = 0
        local charCode = ""
        if curByte > 0 and curByte <= 127 then
            byteCount = 1
            charCode = curByte
        elseif curByte >= 192 and curByte < 223 then
            byteCount = 2
            local byte2 = string.byte(utf8Text, i + 1)
            charCode = (curByte - 192) * 64 + (byte2 - 128)
        elseif curByte >= 224 and curByte < 239 then
            byteCount = 3
            local byte2 = string.byte(utf8Text, i + 1)
            local byte3 = string.byte(utf8Text, i + 2)
            charCode = (curByte - 224) * 4096 + (byte2 - 128) * 64 + (byte3 - 128)
        end
        if byteCount > 0 then
            gb2312Text = gb2312Text .. string.char(charCode / 256, charCode % 256)
            i = i + byteCount - 1
        end
    end
    return gb2312Text
end

-- 测试转换函数
local utf8Text = "积水20cm"
local gb2312Text = utf8ToGb2312(utf8Text)
print(gb2312Text)

输出结果为：

积水20cm的GB2312编码