请大家帮忙看看这段"抽奖"代码的思路和含义

Question

小弟我是新手看不大明白啊，能详细说说吗？特别是它如何实现随机抽奖的，谢谢！万分感激～  AssignFile(BaseFile,TextEdit.Text);
  Reset(BaseFile);
  BaseLen:=0;
  While not eof(BaseFile) do
  begin
    Readln(BaseFile,BaseStr);
    BaseLen:=BaseLen+1;
  end;
  CloseFile(BaseFile);
  pickno:=StrToInt(SpinEdit1.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit4.Text);
  if pickno=0 then
  begin
    ShowMessage('您设的抽奖数量为0，程序不能执行下去！');
    Exit;
  end;  if PickNo>BaseLen then
  begin
    ShowMessage('文本文件中的资料只有'+IntToStr(BaseLen)+'行，您设置的抽奖数量却为'+IntToStr(PickNo)+'！  请重新设置。');
    Exit;
  end;  Gauge.Progress:=0;
  for I:=1 to PickNo do
  begin
    Gauge.Progress:=50*I Div PickNo;
    j:=0;
    randomize;
    RandomBaseLen:=Random(BaseLen)+1;
    while J<I do
    begin
      if inttostr(RandomBaseLen)<>Pick[J] then
        J:=J+1
      else
      begin
        Randomize;
        RandomBaseLen:=Random(BaseLen)+1;
        J:=0
      end;
    end;
    Pick[I]:=IntToStr(RandomBaseLen);
  end;  AssignFile(BaseFile,TextEdit.Text);
  Reset(BaseFile);AssignFile(BaseFile,TextEdit.Text);
  Reset(BaseFile);
  for J:=1 to BaseLen do
  begin
    Gauge.Progress:=50+50*J Div BaseLen;
    Readln(BaseFile,BaseStr);
    for I:=1 to PickNo do
    begin
    if IntToStr(J)=Pick[I] then
      begin
        if I<=StrToInt(SpinEdit1.Text) then
        begin
          PickStr[I]:=BaseStr;
          break;
        end;
        if (I<=StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I>StrToInt(SpinEdit1.Text)) then
        begin
          PickStr[I]:=BaseStr;
          break;
        end;
        if (I<=StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I>StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) then
        begin
          PickStr[I]:=BaseStr;
          break;
        end;
        if (I<=StrToInt(SpinEdit4.Text)+StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I>StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) then
        begin
          PickStr[I]:=BaseStr;
          break;
        end;
      end;
    end;
  end;
  CloseFile(BaseFile); 

Answer 1

AssignFile(BaseFile,TextEdit.Text); 
  Reset(BaseFile); 
  BaseLen:=0; 
  While not eof(BaseFile) do 
  begin 
    Readln(BaseFile,BaseStr); 
    BaseLen:=BaseLen+1; //看看文件有多少行
  end; 
  CloseFile(BaseFile);   //取得抽奖数量，如果为0则退出，4个SpinEdit1里是什么，暂时还不知道，应该是和数量有关系的东西吧
  pickno:=StrToInt(SpinEdit1.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit4.Text); 
  if pickno=0 then 
  begin 
    ShowMessage( '您设的抽奖数量为0，程序不能执行下去！ '); 
    Exit; 
  end;   if PickNo >BaseLen then //设定抽奖数量必须大于行数，具体什么资料，还不知道
  begin 
    ShowMessage( '文本文件中的资料只有 '+IntToStr(BaseLen)+ '行，您设置的抽奖数量却为 '+IntToStr(PickNo)+ '！  请重新设置。 '); 
    Exit; 
  end;   Gauge.Progress:=0;//初始化进度条的位置为0  
 for I:=1 to PickNo do //在这儿开始抽足够数量的奖  begin 
    Gauge.Progress:=50*I Div PickNo; 
    j:=0; 
    randomize; 
    //现在开始抽奖，随机行号，即那个奖品，要么就是空奖了，哈
    RandomBaseLen:=Random(BaseLen)+1; //在这儿明白了，文本文件中的东西应该是奖品什么的东西，行数应该是奖品数量的意思
    while J <I do 
    begin 
      if inttostr(RandomBaseLen) < >Pick[J] then 
        J:=J+1 
      else 
      begin 
        Randomize; 
        RandomBaseLen:=Random(BaseLen)+1; 
        J:=0 
      end; 
    end; 
    Pick[I]:=IntToStr(RandomBaseLen);//这个大循环，还没搞清楚，下面的东西交给同志们吧，歇歇，哈 
  end;   AssignFile(BaseFile,TextEdit.Text); 
  Reset(BaseFile);AssignFile(BaseFile,TextEdit.Text); 
  Reset(BaseFile); 
  for J:=1 to BaseLen do 
  begin 
    Gauge.Progress:=50+50*J Div BaseLen; 
    Readln(BaseFile,BaseStr); 
    for I:=1 to PickNo do 
    begin 
    if IntToStr(J)=Pick[I] then 
      begin 
        if I <=StrToInt(SpinEdit1.Text) then 
        begin 
          PickStr[I]:=BaseStr; 
          break; 
        end; 
        if (I <=StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I >StrToInt(SpinEdit1.Text)) then 
        begin 
          PickStr[I]:=BaseStr; 
          break; 
        end; 
        if (I <=StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I >StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) then 
        begin 
          PickStr[I]:=BaseStr; 
          break; 
        end; 
        if (I <=StrToInt(SpinEdit4.Text)+StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) and (I >StrToInt(SpinEdit3.Text)+StrToInt(SpinEdit2.Text)+StrToInt(SpinEdit1.Text)) then 
        begin 
          PickStr[I]:=BaseStr; 
          break; 
        end; 
      end; 
    end; 
  end; 
  CloseFile(BaseFile); 

Answer 2

谢谢hys_427朋友
还请大家多多帮忙啊