delphi中如何动态向枚举类型中添加值

我的意思是，能不能先定一个空的枚举类型然后，程序运行后动态往里面添加值，最后再用一个已经知道的值去判断它是不是在枚举类型当中。要有代码。

Set operators
Operator Operation Operand types Result type Example
+ union set set Set1 + Set2
- difference set set S - T
* intersection set set S * T
<= subset set Boolean Q <= MySet
>= superset set Boolean S1 >= S2
= equality set Boolean S2 = MySet
<> inequality set Boolean MySet <> S1
in membership ordinal, set Boolean A in Set1

用in操作符啊。

in

test.dpr.18: e:=meval1; 0040a179 33db    xor ebx,ebx test.dpr.20: writeln(ord(e));    //显示0 0040a17b 0fb6d3    movzx edx,bl 0040a17e a14cbc4000    mov eax,[$0040bc4c] 0040a183 e88098ffff    call @write0long 0040a188 e8a798ffff    call @writeln 0040a18d e8828fffff    call @_iotest test.dpr.22: e:=meval3; 0040a192 33db    xor ebx,ebx test.dpr.24: writeln(ord(e));    //显示0 0040a194 0fb6d3    movzx edx,bl 0040a197 a14cbc4000    mov eax,[$0040bc4c] 0040a19c e86798ffff    call @write0long 0040a1a1 e88e98ffff    call @writeln 0040a1a6 e8698fffff    call @_iotest test.dpr.26: writeln(ord(low(e)));  //显示0 0040a1ab a14cbc4000    mov eax,[$0040bc4c] 0040a1b0 33d2    xor edx,edx 0040a1b2 e85198ffff    call @write0long 0040a1b7 e87898ffff    call @writeln 0040a1bc e8538fffff    call @_iotest test.dpr.28: writeln(ord(high(e)));   //显示1 0040a1c1 a14cbc4000    mov eax,[$0040bc4c] 0040a1c6 ba01000000    mov edx,$00000001 0040a1cb e83898ffff    call @write0long 0040a1d0 e85f98ffff    call @writeln 这是对应的汇编代码, low(e), high(e)都是直接赋值0， 1的