[求助][求助]如何实现变量是否在数字段的判断 - 编程论坛

#2

sgliuxiu2007-02-07 17:41

用in

#3

sgliuxiu2007-02-07 17:49

我可能理解错了,如果是判断它是不是在什么之间，用if (var1>=0 and var1<=70) then...
如果是判断它在不在0--70里面,就用 in

[此贴子已经被作者于2007-2-7 17:50:06编辑过]

#4

mervynlove2007-02-07 18:30

谢谢，用in如何写？

if VAR1 in 1..70 then

这样好像不行哦

#5

sgliuxiu2007-02-07 19:31

if var1 in [ 1..70] then

#6

sgliuxiu2007-02-07 19:38

你在delphi里面找关于集合的内容

我找到了点，你看看.

Because of the size limitations for base types, set types are usually defined with subranges. For example, the declarations

type
TSomeInts = 1..250;
TIntSet = set of TSomeInts;

create a set type called TIntSet whose values are collections of integers in the range from 1 to 250. You could accomplish the same thing with

type TIntSet = set of 1..250;

Given this declaration, you can create a sets like this:

var Set1, Set2: TIntSet;
...
Set1 := [1, 3, 5, 7, 9];
Set2 := [2, 4, 6, 8, 10]

You can also use the set of ... construction directly in variable declarations:

var MySet: set of 'a'..'z';
...
MySet := ['a','b','c'];

Other examples of set types include

set of Byte
set of (Club, Diamond, Heart, Spade)
set of Char;

The in operator tests set membership:

if 'a' in MySet then ... { do something } ;

Every set type can hold the empty set, denoted by [].