如何知道某年某月一共有几天？

Question

MonthDays常量保存每个月有多少天,类型如下:
Type PDayTable = ^TDayTable;
Type TDayTAble= Array[1..12] of Word;
Const MonthDays:array of[Boolean] of TDayTable;

Answer 1

Day1,Day2:TDateTime;
  Days:Integer;  Days:=Abs(Trunc(Day2)-Trunc(Day1));
用下月一号－当月一号

Answer 2

function GetMonthDays(iYear,iMonth:integer):integter;
const
    Days:array[1..12] of integer = ('31','28','31','30','31','30','31','31','30','31','30','31');
begin
    if (IsLeapYear(iYear)) and (iMonth=2) then
        Result:=Days[iMonth]+1
    else
        Result:=Days[iMonth];
end;

Answer 3

有一个笨办法
我试着写写：
function GetDays(y,m:integer):integer;
var
  i,Wy,Wm,Wr:integer; 
  Workdate:tdate;
begin
  i:=1;
  if (y<0) or (m<0) then
  begin
    result:=-1;
    exit;
  end;
  encodedate(workdate,y,m,1);
  Wm:=m;
  while Wm=m do
  begin
    inc(i);
    incday(workdate);
    decodedate(workdate,wy,wm,wr);
  end;
  result:=i;
end;

Answer 4

定义错了，应该是：
function GetMonthDays(iYear,iMonth:integer):integer;
const
    Days:array[1..12] of integer = (31,28,31,30,31,30,31,31,30,31,30,31);
begin
    if (IsLeapYear(iYear)) and (iMonth=2) then
        Result:=Days[iMonth]+1
    else
        Result:=Days[iMonth];
end;

Answer 5

Delphi6函数
DaysInAMonth(2002,2)

Answer 6

myxfang:
D6哪有daysinamonth这个函数阿？

Answer 7

myxfang(小方)的方法是对的。再请教一下，如何将实型转换为整型？