MQL4参考 标准常量,列举和架构 对象常量 对象可见性

Visibility of Objects

The combination of object visibility flags determines chart timeframes, where the object is visible. To set/get the value of the OBJPROP_TIMEFRAMES property, you can use the ObjectSet()/ObjectGet or ObjectSetInteger()/ObjectGetInteger() functions.

ID

Value

Description

OBJ_NO_PERIODS, EMPTY

-1

The object is not drawn in all timeframes

OBJ_PERIOD_M1

0x0001

The object is drawn in 1-minute chart

OBJ_PERIOD_M5

0x0002

The object is drawn in 5-minute chart

OBJ_PERIOD_M15

0x0004

The object is drawn in 15-minute chart

OBJ_PERIOD_M30

0x0008

The object is drawn in 30-minute chart

OBJ_PERIOD_H1

0x0010

The object is drawn in 1-hour chart

OBJ_PERIOD_H4

0x0020

The object is drawn in 4-hour chart

OBJ_PERIOD_D1

0x0040

The object is drawn in day charts

OBJ_PERIOD_W1

0x0080

The object is drawn in week charts

OBJ_PERIOD_MN1

0x0100

The object is drawn in month charts

OBJ_ALL_PERIODS

0x01ff

The object is drawn in all timeframes

Visibility flags can be combined using the symbol "|", for example, the combination of flags OBJ_PERIOD_M15|OBJ_PERIOD_H1 means that the object will be visible on the 15-minute and hourly timeframes.

Example:

void OnStart()
  {
//---
   string highlevel="PreviousDayHigh";
   string lowlevel="PreviousDayLow";
   double prevHigh;           // The previous day High
   double prevLow;            // The previous day Low
   double highs[],lows[];     // Arrays for High and Low
 
//--- Reset the last error
   ResetLastError();
//--- Get the last 2 High values on the daily timeframe
   int highsgot=CopyHigh(Symbol(),PERIOD_D1,0,2,highs);
   if(highsgot>0) // If copying was successful
     {
      Print("High prices for the last 2 days were obtained successfully");
      prevHigh=highs[0]; // The previous day High
      Print("prevHigh = ",prevHigh);
      if(ObjectFind(0,highlevel)<0) // Object with the name highlevel not found
        {
         ObjectCreate(0,highlevel,OBJ_HLINE,0,0,0); // Create the Horizontal Line object
        }
      //--- Set value for the price level for the line highlevel
      ObjectSetDouble(0,highlevel,OBJPROP_PRICE,0,prevHigh);
      //--- Set the visibility only PERIOD_M15 and PERIOD_H1
      ObjectSetInteger(0,highlevel,OBJPROP_TIMEFRAMES,OBJ_PERIOD_M15|OBJ_PERIOD_H1);
     }
   else
     {
      Print("Could not get High prices over the past 2 days, Error = ",GetLastError());
     }
 
//--- Reset the last error
   ResetLastError();
//--- Get the 2 days values Low on the daily timeframe
   int lowsgot=CopyLow(Symbol(),PERIOD_D1,0,2,lows);
   if(lowsgot>0) // If copying was successful
     {
      Print("Low prices for the last 2 days were obtained successfully");
      prevLow=lows[0]; // The previous day Low
      Print("prevLow = ",prevLow);
      if(ObjectFind(0,lowlevel)<0) // Object with the name lowlevel not found
        {
         ObjectCreate(0,lowlevel,OBJ_HLINE,0,0,0); // Create the Horizontal Line object
        }
      //--- Set value for the price level for the line lowlevel
      ObjectSetDouble(0,lowlevel,OBJPROP_PRICE,0,prevLow);
      //--- Set the visibility only PERIOD_M15 and PERIOD_H1
      ObjectSetInteger(0,lowlevel,OBJPROP_TIMEFRAMES,OBJ_PERIOD_M15|OBJ_PERIOD_H1);
     }
   else Print("Could not get Low prices for the last 2 days, Error = ",GetLastError());
 
   ChartRedraw(0); // redraw the chart forcibly
  }

See also

PeriodSeconds, Period, Chart timeframes, Date and Time