如何POP3邮件的收取? 急！

Question

我用DELPHI + INDY 编了个"POP3协议收到邮件"程序.
但收到的邮件其标题、发信人地址都是乱码。英文都是好的。

Answer 1

通过如下函数对Subject或其它信息进行处理。
CheckTxt(Msg.Subject) 
CheckTxt(Msg.From.Text)
-----------------------------------------
function CheckTxt(s: string): string;
var
      s1,s2,s3: integer;
      t,v: string;
      Encoding: char;
      hex,step: integer;
      a1: array[1..4] of byte;
      b1: array[1..3] of byte;
      j: integer;
      byte_ptr,real_bytes: integer;
begin
    s1:=Pos('=?',s);
    s2:= 1 ;
    hex:= 0 ;
    if s1>0 then
        begin
          for s2:=Length(s)-1 downto 1 do  if Copy(s,s2,2)='?=' then Break;
        end;
    if (s1=0) or (s2=1) then  begin Result:=s;   Exit; end;
    t:=Copy(s,s1+2,s2-2-s1);
    s3:=Pos('?',t);
    Delete(t,1,s3);
    if(t='')then
        begin
            Result:= s;
            Exit ;
        end ;
    Encoding:=t[1];
    Delete(t,1,2);
    v:='';
    step:=0;
    case Encoding of
    'Q':
    while t<>'' do
    begin
    case step of
    0:
        begin
          case t[1] of
          '_': v:=v+' ';
          '=': step:=1;
          else v:=v+t[1];
          end;
        end;
    1:
        begin
            if t[1]<='9' then hex:=(Ord(t[1])-Ord('0'))*16
            else hex:=(Ord(t[1])-55)*16;
            step:=2;
        end;
    2:
    begin
        if t[1]<='9' then hex:=hex+(Ord(t[1])-Ord('0'))
        else hex:=hex+Ord(t[1])-55;
        v:=v+Chr(hex);
        step:=0;
    end;
    end;
    Delete(t,1,1);
    end;
    'B':
    begin
        byte_ptr:=0;
        for j:=1 to Length(t) do
        begin
          Inc(byte_ptr);
          case t[j] of
            'A'..'Z': a1[byte_ptr]:=Ord(t[j])-65;
            'a'..'z': a1[byte_ptr]:=Ord(t[j])-71;
            '0'..'9': a1[byte_ptr]:=Ord(t[j])+4;
            '+': a1[byte_ptr]:=62;
            '/': a1[byte_ptr]:=63;
            '=': a1[byte_ptr]:=64;
          end;
          if byte_ptr=4 then
            begin
                byte_ptr:=0;
                real_bytes:=3;
                if a1[1]=64 then real_bytes:=0;
                if a1[3]=64 then
                    begin
                        a1[3]:=0;
                        a1[4]:=0;
                        real_bytes:=1;
                    end;
                if a1[4]=64 then
                    begin
                      a1[4]:=0;
                      real_bytes:=2;
                    end;
                b1[1]:=a1[1]*4+(a1[2] div 16);
                b1[2]:=(a1[2] mod 16)*16+(a1[3]div 4);
                b1[3]:=(a1[3] mod 4)*64 +a1[4];
                if(real_bytes>0)then  v:= v + chr(b1[1]) ;
                if(real_bytes>1)then  v:= v + chr(b1[2]) ;
                if(real_bytes>2)then  v:= v + chr(b1[3]) ;
                end;
            end;
        end;
        end;
    Result:=Copy(s,1,s1-1)+v+Copy(s,s2+2,999);
end;