Problem knowing how to write yesturday's high close opens continuously as indicator?

It is not clear whether you intend to draw your lines with a trend line or a buffer

   ycloseBuffer[i] = iClose(_Symbol,PERIOD_D1,1);
   yhighBuffer[i] = iHigh(_Symbol,PERIOD_D1,1); 
   ylowBuffer[i] = iLow(_Symbol,PERIOD_D1,1); 

 These will all get values for index 1 on the daily chart, not related to i at all

   datetime timeStart = CreateDateTime(0,0);    
   datetime timeEnd = CreateDateTime(23,0);

 We don't know what these functions do, but again do not appear to relate to i

   ObjectCreate(ob_yc,OBJ_TREND,0,timeStart,yclose,timeEnd,yclose); 
   ObjectCreate(ob_yh,OBJ_TREND,0,timeStart,yhigh,timeEnd,yhigh); 
   ObjectCreate(ob_yl,OBJ_TREND,0,timeStart,ylow,timeEnd,ylow);    

 Where do the values for yclose etc come from?

Ive included the whole code so as you can see where the values come from. Im trying to use iClose(_Symbol,PERIOD_D1,1); to draw a trend line as a buffer setting.  

The datetime timeStart = CreateDateTime(0,0); is found in an include file and sets the time coordinates for the parameters at ObjectCreate(ob_yc,OBJ_TREND,0,timeStart,yclose,timeEnd,yclose);    

yclose  is set at start of code as double yclose = iClose(_Symbol,PERIOD_D1,1);  

. 

#include <Mql4Book\Timer.mqh>
CTimer Timer;

#property indicator_chart_window
#property indicator_buffers 3
#property indicator_plots 3

//--- buffers
double ycloseBuffer[];     
double yhighBuffer[];     
double ylowBuffer[];
                          
double yclose = iClose(_Symbol,PERIOD_D1,1); 
double yhigh = iHigh(_Symbol,PERIOD_D1,1); 
double ylow = iLow(_Symbol,PERIOD_D1,1); 

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int OnInit()
  {
//---indicator buffer mapping
   SetIndexBuffer(0,ycloseBuffer);
   SetIndexBuffer(1,yhighBuffer);   
   SetIndexBuffer(2,ylowBuffer);     
//---
   return(INIT_SUCCEEDED);
  }

//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
   {
//---  
   ArraySetAsSeries(ycloseBuffer,true); 
   ArraySetAsSeries(yhighBuffer,true);      
   ArraySetAsSeries(ylowBuffer,true);    

   int bars = rates_total - 1; 
   if(prev_calculated > 0) bars = rates_total - prev_calculated; 
   
   for(int i = bars; i >= 0; i--) 
  {
   ycloseBuffer[i] = iClose(_Symbol,PERIOD_D1,1);   
   yhighBuffer[i] = iHigh(_Symbol,PERIOD_D1,1); 
   ylowBuffer[i] = iLow(_Symbol,PERIOD_D1,1); 

   datetime timeStart = CreateDateTime(0,0);    
   datetime timeEnd = CreateDateTime(23,0);

   string ob_yc = "ycloseline "+TimeToStr(timeStart);    
   string ob_yh = "yhighline "+TimeToStr(timeStart);   
   string ob_yl = "ylowline "+TimeToStr(timeStart); 

   ObjectCreate(ob_yc,OBJ_TREND,0,timeStart,yclose,timeEnd,yclose); 
   ObjectCreate(ob_yh,OBJ_TREND,0,timeStart,yhigh,timeEnd,yhigh); 
   ObjectCreate(ob_yl,OBJ_TREND,0,timeStart,ylow,timeEnd,ylow);    

   ObjectSet(ob_yc,OBJPROP_STYLE,STYLE_DASH); // This edits the lines regardless 
   ObjectSet(ob_yh,OBJPROP_STYLE,STYLE_DASH);  
   ObjectSet(ob_yl,OBJPROP_STYLE,STYLE_DASH); 
   
   ObjectSet(ob_yc,OBJPROP_RAY,false);  
   ObjectSet(ob_yh,OBJPROP_RAY,false);  
   ObjectSet(ob_yl,OBJPROP_RAY,false);         
  }    
     
//--- return value of prev_calculated for next call
   return(rates_total);
   }

//+------------------------------------------------------------------+