海康威视摄像头SDK[Delphi]-错误7网络\u DVR\u网络\u连接失败

我无法连接到hikvison摄像头，NET_DVR_Login_V30返回-1，NET_DVR_GetLastError返回7： “网络\u DVR\u网络\u连接失败\u连接设备失败。设备脱机或网络连接超时。”

摄像头100%在线并已配置，我可以使用ClientDemo.exe成功连接

在wireshark中，我看到它甚至不尝试连接

type
  LPNET_DVR_DEVICEINFO_V30 = ^NET_DVR_DEVICEINFO_V30;

  NET_DVR_DEVICEINFO_V30 = Record
    sSerialNumber: array [0 .. 47] of BYTE;
    byAlarmInPortNum: BYTE;
    byAlarmOutPortNum: BYTE;
    byDiskNum: BYTE;
    byDVRType: BYTE;
    byChanNum: BYTE;
    byStartChan: BYTE;
    byAudioChanNum: BYTE;
    byIPChanNum: BYTE;
    byZeroChanNum: BYTE;
    byMainProto: BYTE;
    bySubProto: BYTE;
    bySupport: BYTE;
    bySupport1: BYTE;
    byRes1: BYTE;
    wDevType: Word;
    byRes2: array [0 .. 15] of BYTE;
  end;

  (...)

var
  Form1: TForm1;
  ErrorValues: LongWord;
  lUserID: LONG;
  struDeviceInfo: NET_DVR_DEVICEINFO_V30;
  DVRIP, DVRUserName, DVRPassWord: String;


function NET_DVR_Init(): boolean; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_Init';

function NET_DVR_Cleanup(): boolean; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_Cleanup';

function NET_DVR_SetConnectTime(dwWaitTime, dwTryTimes: DWORD): boolean;
  stdcall; external 'HCNetSDK.dll' name 'NET_DVR_SetConnectTime';

function NET_DVR_SetReconnect(dwInterval: DWORD; bEnableRecon: boolean)
  : boolean; stdcall; external 'HCNetSDK.dll' name 'NET_DVR_SetReconnect';

function NET_DVR_GetLastError(): LongWord; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_GetLastError';

function NET_DVR_Login_V30(sDVRIP: PChar; wDVRPort: Word; sUserName: PChar;
  sPassword: PChar; lpDeviceInfo: LPNET_DVR_DEVICEINFO_V30): LONG; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_Login_V30';

function NET_DVR_Logout_V30(lUserID: LONG): boolean; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_Logout_V30';


implementation

{$R *.dfm}


procedure TForm1.Button1Click(Sender: TObject);
begin
  DVRIP := 'xxx.xxx.xxx.xxx';
  DVRUserName := 'demo';
  DVRPassWord := '12345';

  NET_DVR_Init();

  NET_DVR_SetConnectTime(2000, 1);
  NET_DVR_SetReconnect(10000, true);

  lUserID := NET_DVR_Login_V30(PChar(DVRIP), 8000, PChar(DVRUserName),
    PChar(DVRPassWord), @struDeviceInfo);
  Memo1.Lines.Add('lUserID:' + inttostr(lUserID));

  ErrorValues := NET_DVR_GetLastError();
  Memo1.Lines.Add('ErrorValues:' + inttostr(ErrorValues));

  NET_DVR_Logout_V30(lUserID);
  NET_DVR_Cleanup();

end;

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关于

要使其正常工作，原始代码需要两个修复：
1.将变量声明从字符串更正为AnsiString
2.将字符串作为PAnsiChar传递给dll（如G Wimpassinger所指）

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您使用哪种Delphi版本？也许你需要使用PAnsiChar而不是PChar。我不知道SDK.Delphi10.1柏林版。PAnsiChar而不是PChar没有区别。上面在互联网上找到的代码很旧。不熟悉SDK，但你有实际的DVR设置吗？如果没有，也许API有一种直接连接摄像头的方法……SDK由2个dll组成，其基本形式为。我使用与ClientDemo相同的dll，可以正确连接。Camera有一个http上的API，它可以正常工作，但它有一些缺点，所以我尝试使用SDK。@Gwinger PAnsiChar是关键！我没有纠正的一件事是从字符串到ansisting的变量声明。谢谢。

DVRIP, DVRUserName, DVRPassWord: AnsiString;
...

function NET_DVR_Login_V30(sDVRIP: PAnsiChar; wDVRPort: Word; sUserName: PAnsiChar;
  sPassword: PAnsiChar; lpDeviceInfo: LPNET_DVR_DEVICEINFO_V30): LONG; stdcall;
  external 'HCNetSDK.dll' name 'NET_DVR_Login_V30';
...

lUserID := NET_DVR_Login_V30(PAnsiChar(DVRIP), 8000, PAnsiChar(DVRUserName),
  PAnsiChar(DVRPassWord), @struDeviceInfo);