如何使用“case”语句而不是“if”语句测试值是否在范围内？

Question

可以将以下if语句转换为case语句吗？

if (Number >= 5) and (Number <= 10) then
  lblAnswer.Caption := 'in range'
else
  lblAnswer.Caption := 'out of range';

---

我的回答：

是的，它可以

case (number >= 5) and (Number <= 10) of
  lblAnswer.Caption := 'in range';
  lblAnswer.Caption := 'out of range';
end;

这是对的吗？

Answer 1

如果Number有一些整数数据类型，那么：

case number of
5 .. 10: lblAnswer.Caption := 'in range';
else     lblAnswer.Caption := 'out of range';
end;

Answer 2

一个小小的修正：

case (number >= 5) and (Number <= 10) of
  true:lblAnswer.Caption := 'in range';
  false:lblAnswer.Caption := 'out of range';
end;

Answer 3

Function InRange (Lo,Hi,Val : Integer) : Boolean;
Begin
 Result := (Val>=Lo)And(Val<=Hi);
End;