DatabaseBindArray

bool  DatabaseBind(
   int  request,      // DatabasePrepare中创建的请求句柄
   int  index,        // 请求中的参数索引
   T&   array[]       // 数组设为参数值
   );

     INSERT INTO table VALUES (?,?,?)

//+------------------------------------------------------------------+
//| 脚本程序起始函数                                                   |
//+------------------------------------------------------------------+
void OnStart()
  {
//--- 打开用于选择带有DAT扩展名的文件的对话框
   string selected_files[];
   if(!FileSelectDialog("Select files to download", NULL,
                       "Data files (*.dat)|*.dat|All files (*.*)|*.*",
                       FSD_ALLOW_MULTISELECT, selected_files, "tester.dat")>0)
     {
      Print("Files not selected. Exit");
      return;
     }
//--- 获取文件大小
   ulong filesize[];
   int filehandle[];
   int files=ArraySize(selected_files);
   ArrayResize(filesize, files);
   ZeroMemory(filesize);
   ArrayResize(filehandle, files);
   double total_size=0;
   for(int i=0; i<files; i++)
     {
      filehandle[i]=FileOpen(selected_files[i], FILE_READ|FILE_BIN);
      if(filehandle[i]!=INVALID_HANDLE)
        {
         filesize[i]=FileSize(filehandle[i]);
         //PrintFormat("%d, %s handle=%d %d bytes", i, selected_files[i], filehandle[i], filesize[i]);
         total_size+=(double)filesize[i];
        }
     }
//--- 检查常规文件大小
   if(total_size==0)
     {
      PrintFormat("Total files size is 0. Exit");
      return;
     }
 
//--- 在常规程序端文件夹中创建或打开数据库
   string filename="dat_files.sqlite";
   int db=DatabaseOpen(filename, DATABASE_OPEN_READWRITE | DATABASE_OPEN_CREATE);
   if(db==INVALID_HANDLE)
     {
      Print("DB: ", filename, " open failed with code ", GetLastError());
      return;
     }
   else
      Print("Database: ", filename, " opened successfully");
//--- 如果FILES表格已存在，请将其删除
   if(DatabaseTableExists(db, "FILES"))
     {
      //--- 删除表格
      if(!DatabaseExecute(db, "DROP TABLE FILES"))
        {
         Print("Failed to drop table FILES with code ", GetLastError());
         DatabaseClose(db);
         return;
        }
     }
//--- 创建FILES表格
   if(!DatabaseExecute(db, "CREATE TABLE FILES("
                       "NAME           TEXT NOT NULL,"
                       "SIZE           INT  NOT NULL,"
                       "PERCENT_SIZE   REAL NOT NULL,"
                       "DATA           BLOB NOT NULL);"))
     {
      Print("DB: failed to create table FILES with code ", GetLastError());
      DatabaseClose(db);
      return;
     }
//--- 显示FILES表格中所有字段列表
   if(DatabasePrint(db, "PRAGMA TABLE_INFO(FILES)", 0)<0)
     {
      PrintFormat("DatabasePrint(\"PRAGMA TABLE_INFO(FILES)\") failed, error code=%d at line %d", GetLastError(), __LINE__);
      DatabaseClose(db);
      return;
     }
 
//--- 创建参数化请求，将文件添加到FILES表格中
   string sql="INSERT INTO FILES (NAME,SIZE,PERCENT_SIZE,DATA)"
              " VALUES (?1,?2,?3,?4);"; // 请求参数
   int request=DatabasePrepare(db, sql);
   if(request==INVALID_HANDLE)
     {
      PrintFormat("DatabasePrepare() failed with code=%d", GetLastError());
      Print("SQL request: ", sql);
      DatabaseClose(db);
      return;
     }
 
//--- 检查所有文件并将其添加到FILES表格中
   bool request_error=false;
   DatabaseTransactionBegin(db);
   int count=0;
   uint size;
   for(int i=0; i<files; i++)
     {
      if(filehandle[i]!=INVALID_HANDLE)
        {
         char data[];
         size=FileReadArray(filehandle[i], data);
         if(size==0)
           {
            PrintFormat("FileReadArray(%s) failed with code %d", selected_files[i], GetLastError());
            continue;
           }
 
         count++;
         //--- 在将文件添加到表格之前设置参数值
         if(!DatabaseBind(request, 0, selected_files[i]))
           {
            PrintFormat("DatabaseBind() failed at line %d with code=%d", __LINE__, GetLastError());
            request_error=true;
            break;
           }
         if(!DatabaseBind(request, 1, size))
           {
            PrintFormat("DatabaseBind() failed at line %d with code=%d", __LINE__, GetLastError());
            request_error=true;
            break;
           }
         if(!DatabaseBind(request, 2, double(size)*100./total_size))
           {
            PrintFormat("DatabaseBind() failed at line %d with code=%d", __LINE__, GetLastError());
            request_error=true;
            break;
           }
         if(!DatabaseBindArray(request, 3, data))
           {
            PrintFormat("DatabaseBind() failed at line %d with code=%d", __LINE__, GetLastError());
            request_error=true;
            break;
           }
         //--- 执行插入条目的请求并检查错误
         if(!DatabaseRead(request)&&(GetLastError()!=ERR_DATABASE_NO_MORE_DATA))
           {
            PrintFormat("DatabaseRead() failed with code=%d", GetLastError());
            DatabaseFinalize(request);
            request_error=true;
            break;
           }
         else
            PrintFormat("%d. %s: %d bytes", count, selected_files[i],size);
         //--- 在下一次参数更新之前重置请求
         if(!DatabaseReset(request))
           {
            PrintFormat("DatabaseReset() failed with code=%d", GetLastError());
            DatabaseFinalize(request);
            request_error=true;
            break;
           }
        }
     }
//--- 交易事务状态
   if(request_error)
     {
      PrintFormat("Table FILES: failed to add %d files", count);
      DatabaseTransactionRollback(db);
      DatabaseClose(db);
      return;
     }
   else
     {
      DatabaseTransactionCommit(db);
      PrintFormat("Table FILES: added %d files", count);
     }
 
//--- 关闭数据库文件并告知
   DatabaseClose(db);
   PrintFormat("Database: %s created and closed", filename);
  }