CAD从二制流数据中加载图形（com接口Delphi语言）

主要用到函数说明：

_DMxDrawX::ReadBinStream

从二制流数据中加载图形，详细说明如下：

Delphi代码实现如下：

            functionOleToMStream(OV:OleVariant): TMemoryStream;            var              Data: PByteArray;              Size: integer;            beginResult:=TMemoryStream.Create;                     try                       Size:=VarArrayHighBound(OV,1)-VarArrayLowBound(OV,1)+1;                       Data:=VarArrayLock(OV);                         try                           Result.Position:=0;                           Result.WriteBuffer(Data^,Size);                         finally                           VarArrayUnlock(OV);                         end;                     except                       Result.Free;Result:=nil;                     end;                   end;                    functionMStreamToOle(Strm:TMemoryStream): OleVariant;                   var                     Data: PByteArray;                   beginResult:= VarArrayCreate([0,   Strm.Size   -   1],   varByte);                     Data:=   VarArrayLock(Result);                     try                         Strm.Position   :=   0;                         Strm.ReadBuffer(Data^,   Strm.Size);                     finally                         VarArrayUnlock(Result);                     end;                   end;                    procedure TForm2.Button6Click(Sender: TObject);                   var                     aryData:OleVariant;                     memStream : TMemoryStream ;                     aryReadData:     OleVariant;                   begin                       // 写到内存流                      MxDrawX1.WriteBinStream(aryData,'',23);                      memStream := OleToMStream(aryData);                       // 从内存流加载                      aryReadData := MStreamToOle( memStream);                      MxDrawX1.ReadBinStream(aryData,'',23);                    end;