當我嘗試使用此線程但我看不到問題時,我總是收到「線程錯誤:句柄無效(6)」。如果可以,請幫助,謝謝!線程中的句柄錯誤無效
stackoverlow抱怨說我沒有足夠的解釋。所以,我創建了一個沒有任何錯誤編譯的線程類,但是當我用execute調用它時似乎運行正常,但是在析構函數中拋出了這個錯誤。
tdownloadthread = class(tthread)
private
furl,
ffilename,
fmsg: string;
fdl: tidhttp;
readings,bpstotal,avgbps: int64;
fpercent: word;
fsuccess,fcanceled: boolean;
start: tdatetime;
fspeed,fremaining: string;
public
constructor create(url,filename: string);
destructor destroy; override;
procedure execute; override;
procedure DlWork(ASender: TObject; AWorkMode: TWorkMode; AWorkCount: Int64);
procedure cancel;
property success: boolean read fsuccess;
property canceled: boolean read fcanceled;
property speed: string read fspeed;
property percent: word read fpercent;
property remaining: string read fremaining;
property msg: string read fmsg;
end;
constructor tdownloadthread.create(url,filename: string);
begin
fsuccess:=false;
fcanceled:=false;
fdl:=tidhttp.Create(nil);
fdl.OnWork:=dlwork;
fdl.HandleRedirects:=true;
furl:=url;
ffilename:=filename;
freeonterminate:=false;
end;
destructor tdownloadthread.Destroy;
begin
fdl.Free;
end;
procedure tdownloadthread.cancel;
begin
fdl.Disconnect;
fcanceled:=true;
end;
procedure tdownloadthread.DlWork(ASender: TObject; AWorkMode: TWorkMode; AWorkCount: Int64);
var
Http: TIdHTTP;
ContentLength: Int64;
i,h,m,esec,sec,rsec,bps: Integer;
f: tdatetime;
begin
Http := TIdHTTP(ASender);
ContentLength := Http.Response.ContentLength;
if (Pos('chunked', LowerCase(Http.Response.ResponseText)) = 0) and
(ContentLength > 0) then
begin
fpercent := trunc(100*(AWorkCount/ContentLength));
esec := secondsbetween(now, start);
if (avgbps > 0) then
begin
i:=contentlength div avgbps;
f:=incsecond(now, i);
rsec:=secondsbetween(now, f);
sec:=rsec - esec;
h:=sec div 3600;
m:=sec div 60 - H * 60;
sec:=sec - (H * 3600 + M * 60) ;
end;
if (esec > 0) then
bps:=(aworkcount div esec)
else
bps:=0;
inc(readings);
inc(bpstotal, bps);
avgbps:=bpstotal div readings;
if (avgbps/1024 < 1024) then
fspeed:=format('%2f KB/s', [avgbps/1024])
else
fspeed:=format('%2f MB/s', [(avgbps div 1024)/1024]);
fremaining:=format('%s m %s s', [zero(m), zero(secno)]);
end;
end;
procedure tdownloadthread.Execute;
var fn,cd: string;
data: tmemorystream;
begin
try
start:=now;
data:=tmemorystream.Create;
fdl.Get(furl, data);
cd:=fdl.Response.ContentDisposition;
if (pos('filename=', cd) > 0) then
fn:=extractfilepath(paramstr(0))+copy(cd, pos('=', cd)+1, length(cd))
else
fn:=ffilename;
data.SaveToFile(fn);
ffilename:=fn;
fsuccess:=true;
data.Free;
except
on e: exception do
begin
fsuccess:=false;
fmsg:=e.Message;
end;
end;
end;
procedure testdownload;
var downloadthread: tdownloadthread;
begin
downloadthread:=tdownloadthread.create('http://www.someurl.com/filename.old',extractfilepath(paramstr(0))+'filename.new');
downloadthread.Execute;
if downloadthread.canceled then showmessage('canceled');
if downloadthread.success then showmessage('success');
if not downloadthread.success then showmessage('error: '+downloadthread.msg);
downloadthread.Free;
end;
您不應該從主線程(或者所有順便說一句)調用線程執行方法。在沒有正確同步的情況下釋放同一過程中的線程將在線程啓動之前結束線程。 –
是的 - 我錯過了呼叫執行()和不合適的免費。我沒有得到那麼多:) –
@MartinJames,添加到你的答案,你發現失蹤的'繼承'畢竟。 –