如何在图表上绘制等距通道

在MetaTrader平台上，开发者通常使用MQL5语言进行图形对象的操作。以下我们提供了创建、移动和删除等距通道的一些基本函数，以帮助开发者更轻松地在图表上操作通道。

1. 创建等距通道：

bool ChannelCreate(const long chart_ID=0,
                   const string name="Channel",
                   const int sub_window=0,
                   datetime time1=0,
                   double price1=0,
                   datetime time2=0,
                   double price2=0,
                   datetime time3=0,
                   double price3=0,
                   const color clr=clrRed,
                   const ENUM_LINE_STYLE style=STYLE_SOLID,
                   const int width=1,
                   const bool fill=false,
                   const bool back=false,
                   const bool selection=true,
                   const bool ray_right=false,
                   const bool hidden=true,
                   const long z_order=0)
{
   ChangeChannelEmptyPoints(time1, price1, time2, price2, time3, price3);
   ResetLastError();
   if(!ObjectCreate(chart_ID, name, OBJ_CHANNEL, sub_window, time1, price1, time2, price2, time3, price3))
   {
      Print(__FUNCTION__,
            ": failed to create an equidistant channel! Error code = ", GetLastError());
      return(false);
   }
   ObjectSetInteger(chart_ID, name, OBJPROP_COLOR, clr);
   ObjectSetInteger(chart_ID, name, OBJPROP_STYLE, style);
   ObjectSetInteger(chart_ID, name, OBJPROP_WIDTH, width);
   ObjectSetInteger(chart_ID, name, OBJPROP_BACK, back);
   ObjectSetInteger(chart_ID, name, OBJPROP_SELECTABLE, selection);
   ObjectSetInteger(chart_ID, name, OBJPROP_SELECTED, selection);
   ObjectSetInteger(chart_ID, name, OBJPROP_RAY_RIGHT, ray_right);
   ObjectSetInteger(chart_ID, name, OBJPROP_HIDDEN, hidden);
   ObjectSetInteger(chart_ID, name, OBJPROP_ZORDER, z_order);
   return(true);
}

2. 更改通道的锚点位置：

bool ChannelPointChange(const long chart_ID=0,
                        const string name="Channel",
                        const int point_index=0,
                        datetime time=0,
                        double price=0)
{
   if(!time) time=TimeCurrent();
   if(!price) price=SymbolInfoDouble(Symbol(), SYMBOL_BID);
   ResetLastError();
   if(!ObjectMove(chart_ID, name, point_index, time, price))
   {
      Print(__FUNCTION__,
            ": failed to move the anchor point! Error code = ", GetLastError());
      return(false);
   }
   return(true);
}

3. 删除等距通道：

bool ChannelDelete(const long chart_ID=0,
                   const string name="Channel")
{
   ResetLastError();
   if(!ObjectDelete(chart_ID, name))
   {
      Print(__FUNCTION__,
            ": failed to delete the channel! Error code = ", GetLastError());
      return(false);
   }
   return(true);
}

4. 更改通道空锚点的位置：

void ChangeChannelEmptyPoints(datetime &time1, double &price1, datetime &time2,
                              double &price2, datetime &time3, double &price3)
{
   if(!time2) time2=TimeCurrent();
   if(!price2) price2=SymbolInfoDouble(Symbol(), SYMBOL_BID);
   if(!time1)
   {
      datetime temp[10];
      CopyTime(Symbol(), Period(), time2, 10, temp);
      time1=temp[0];
   }
   if(!price1) price1=price2+300*SymbolInfoDouble(Symbol(), SYMBOL_POINT);
   if(!time3) time3=time1;
   if(!price3) price3=price2;
}

以上函数提供了对等距通道的基本操作。