script_min_spread_buy

//+------------------------------------------------------------------+
//|                                                      ProjectName |
//|                                      Copyright 2012, CompanyName |
//|                                       http://www.companyname.net |
//+------------------------------------------------------------------+
#property strict
#property show_inputs
//---
extern double mybuystoploss=250;
extern double mybuytakeprofit=750;
extern double mylots=5;
extern double maxspreadslip=0;
//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
void OnStart()
  {
   int ticket=0;
   bool executed=false;
//--- get minimum stop level
   double myminstoplevel=MarketInfo(Symbol(),MODE_STOPLEVEL);
   Print("Minimum Stop Level =",myminstoplevel," points");
   double myprice=Ask;
//--- calculated SL and TP prices must be normalized
   double thebuystoploss=(NormalizeDouble((Bid-Point*mybuystoploss),Digits));
   double thebuytakeprofit=(NormalizeDouble((Bid+Point*mybuytakeprofit),Digits));
//--- place market order to buy lots
   double spreadtarget=(iCustom(Symbol(),1,"spreadmin",0,1))+maxspreadslip;
   Alert("Target for BUY spread = "+DoubleToString(spreadtarget));
//---   
   while(!executed)
     {
      if((MarketInfo(Symbol(),MODE_SPREAD))<=(spreadtarget))
        {
         ticket=OrderSend(Symbol(),OP_BUY,mylots,myprice,0,thebuystoploss,thebuytakeprofit,"My order",1999,0,clrGreen);
         Print("Spread for BUY = "+DoubleToString(MarketInfo(Symbol(),MODE_SPREAD)));
         executed=true;
        }
     }
//---
   if(ticket<0)
     {
      int mylasterror=GetLastError();
      Print("OrderSend Buy failed with error #",IntegerToString(mylasterror)+" "+ErrorDescription(mylasterror));
      Alert("BUY at MIN Spread FAILED!");
     }
   else
      Print("OrderSend BUY MIN Spread Success!");
  }
//+------------------------------------------------------------------+
//| Return Error Code Description                                    |
//+------------------------------------------------------------------+
string ErrorDescription(int error_code)
  {
   string error_string;
//----
   switch(error_code)
     {
      //---- codes returned from trade server
      case 0   : error_string="No error returned";                                                                              break;
      case 1   : error_string="No error returned, but the result is unknown";                                                   break;
      case 2   : error_string="Common error";                                                                                   break;
      case 3   : error_string="Invalid trade parameters";                                                                       break;
      case 4   : error_string="Trade server is busy";                                                                           break;
      case 5   : error_string="Old version of the client terminal";                                                             break;
      case 6   : error_string="No connection with trade server";                                                                break;
      case 7   : error_string="Not enough rights";                                                                              break;
      case 8   : error_string="Too frequent requests";                                                                          break;
      case 9   : error_string="Malfunctional trade operation";                                                                  break;
      case 64  : error_string="Account disabled";                                                                               break;
      case 65  : error_string="Invalid account";                                                                                break;
      case 128 : error_string="Trade timeout";                                                                                  break;
      case 129 : error_string="Invalid price";                                                                                  break;
      case 130 : error_string="Invalid stops";                                                                                  break;
      case 131 : error_string="Invalid trade volume";                                                                           break;
      case 132 : error_string="Market is closed";                                                                               break;
      case 133 : error_string="Trade is disabled";                                                                              break;
      case 134 : error_string="Not enough money";                                                                               break;
      case 135 : error_string="Price changed";                                                                                  break;
      case 136 : error_string="Off quotes";                                                                                     break;
      case 137 : error_string="Broker is busy";                                                                                 break;
      case 138 : error_string="Requote";                                                                                        break;
      case 139 : error_string="Order is locked";                                                                                break;
      case 140 : error_string="Buy orders only allowed";                                                                        break;
      case 141 : error_string="Too many requests";                                                                              break;
      case 145 : error_string="Modification denied because order is too close to market";                                       break;
      case 146 : error_string="Trade context is busy";                                                                          break;
      case 147 : error_string="Expirations are denied by broker";                                                               break;
      case 148 : error_string="The amount of open and pending orders has reached the limit set by the broker";                  break;
      case 149 : error_string="An attempt to open an order opposite to the existing one when hedging is disabled";              break;
      case 150 : error_string="An attempt to close an order contravening the FIFO rule";                                        break;
      //---- MQL Errors
      case 4000: error_string="No error returned";                                                                              break;
      case 4001: error_string="Wrong function pointer";                                                                         break;
      case 4002: error_string="Array index is out of range";                                                                    break;
      case 4003: error_string="No memory for function call stack";                                                              break;
      case 4004: error_string="Recursive stack overflow";                                                                       break;
      case 4005: error_string="Not enough stack for parameter";                                                                 break;
      case 4006: error_string="No memory for parameter string";                                                                 break;
      case 4007: error_string="No memory for temp string";                                                                      break;
      case 4008: error_string="Not initialized string";                                                                         break;
      case 4009: error_string="Not initialized string in array";                                                                break;
      case 4010: error_string="No memory for array string";                                                                     break;
      case 4011: error_string="Too long string";                                                                                break;
      case 4012: error_string="Remainder from zero divide";                                                                     break;
      case 4013: error_string="Zero divide";                                                                                    break;
      case 4014: error_string="Unknown command";                                                                                break;
      case 4015: error_string="Wrong jump (never generated error)";                                                             break;
      case 4016: error_string="Not initialized array";                                                                          break;
      case 4017: error_string="DLL calls are not allowed";                                                                      break;
      case 4018: error_string="Cannot load library";                                                                            break;
      case 4019: error_string="Cannot call function";                                                                           break;
      case 4020: error_string="Expert function calls are not allowed";                                                          break;
      case 4021: error_string="Not enough memory for temp string returned from function";                                       break;
      case 4022: error_string="System is busy (never generated error)";                                                         break;
      case 4023: error_string="DLL-function call critical error";                                                               break;
      case 4024: error_string="Internal error";                                                                                 break;
      case 4025: error_string="Out of memory";                                                                                  break;
      case 4026: error_string="Invalid pointer";                                                                                break;
      case 4027: error_string="Too many formatters in the format function";                                                     break;
      case 4028: error_string="Parameters count exceeds formatters count";                                                      break;
      case 4029: error_string="Invalid array";                                                                                  break;
      case 4030: error_string="No reply from chart";                                                                            break;
      case 4050: error_string="Invalid function parameters count";                                                              break;
      case 4051: error_string="Invalid function parameter value";                                                               break;
      case 4052: error_string="String function internal error";                                                                 break;
      case 4053: error_string="Some array error";                                                                               break;
      case 4054: error_string="Incorrect series array using";                                                                   break;
      case 4055: error_string="Custom indicator error";                                                                         break;
      case 4056: error_string="Arrays are incompatible";                                                                        break;
      case 4057: error_string="Global variables processing error";                                                              break;
      case 4058: error_string="Global variable not found";                                                                      break;
      case 4059: error_string="Function is not allowed in testing mode";                                                        break;
      case 4060: error_string="Function is not allowed for call";                                                               break;
      case 4061: error_string="Send mail error";                                                                                break;
      case 4062: error_string="String parameter expected";                                                                      break;
      case 4063: error_string="Integer parameter expected";                                                                     break;
      case 4064: error_string="Double parameter expected";                                                                      break;
      case 4065: error_string="Array as parameter expected";                                                                    break;
      case 4066: error_string="Requested history data is in updating state";                                                    break;
      case 4067: error_string="Internal trade error";                                                                           break;
      case 4068: error_string="Resource not found";                                                                             break;
      case 4069: error_string="Resource not supported";                                                                         break;
      case 4070: error_string="Duplicate resource";                                                                             break;
      case 4071: error_string="Custom indicator cannot initialize";                                                             break;
      case 4072: error_string="Cannot load custom indicator";                                                                   break;
      case 4099: error_string="End of file";                                                                                    break;
      case 4100: error_string="Some file error";                                                                                break;
      case 4101: error_string="Wrong file name";                                                                                break;
      case 4102: error_string="Too many opened files";                                                                          break;
      case 4103: error_string="Cannot open file";                                                                               break;
      case 4104: error_string="Incompatible access to a file";                                                                  break;
      case 4105: error_string="No order selected";                                                                              break;
      case 4106: error_string="Unknown symbol";                                                                                 break;
      case 4107: error_string="Invalid price";                                                                                  break;
      case 4108: error_string="Invalid ticket";                                                                                 break;
      case 4109: error_string="Trade is not allowed. Enable checkbox Allow live trading in the Expert Advisor properties";      break;
      case 4110: error_string="Longs are not allowed. Check the Expert Advisor properties";                                     break;
      case 4111: error_string="Shorts are not allowed. Check the Expert Advisor properties";                                    break;
      case 4112: error_string="Automated trading by Expert Advisors/Scripts disabled by trade server";                          break;
      case 4200: error_string="Object already exists";                                                                          break;
      case 4201: error_string="Unknown object property";                                                                        break;
      case 4202: error_string="Object does not exist";                                                                          break;
      case 4203: error_string="Unknown object type";                                                                            break;
      case 4204: error_string="No object name";                                                                                 break;
      case 4205: error_string="Object coordinates error";                                                                       break;
      case 4206: error_string="No specified subwindow";                                                                         break;
      case 4207: error_string="Graphical object error";                                                                         break;
      case 4210: error_string="Unknown chart property";                                                                         break;
      case 4211: error_string="Chart not found";                                                                                break;
      case 4212: error_string="Chart subwindow not found";                                                                      break;
      case 4213: error_string="Chart indicator not found";                                                                      break;
      case 4220: error_string="Symbol select error";                                                                            break;
      case 4250: error_string="Notification error";                                                                             break;
      case 4251: error_string="Notification parameter error";                                                                   break;
      case 4252: error_string="Notifications disabled";                                                                         break;
      case 4253: error_string="Notification send too frequent";                                                                 break;
      case 5001: error_string="Too many opened files";                                                                          break;
      case 5002: error_string="Wrong file name";                                                                                break;
      case 5003: error_string="Too long file name";                                                                             break;
      case 5004: error_string="Cannot open file";                                                                               break;
      case 5005: error_string="Text file buffer allocation error";                                                              break;
      case 5006: error_string="Cannot delete file";                                                                             break;
      case 5007: error_string="Invalid file handle (file closed or was not opened)";                                            break;
      case 5008: error_string="Wrong file handle (handle index is out of handle table)";                                        break;
      case 5009: error_string="File must be opened with FILE_WRITE flag";                                                       break;
      case 5010: error_string="File must be opened with FILE_READ flag";                                                        break;
      case 5011: error_string="File must be opened with FILE_BIN flag";                                                         break;
      case 5012: error_string="File must be opened with FILE_TXT flag";                                                         break;
      case 5013: error_string="File must be opened with FILE_TXT or FILE_CSV flag";                                             break;
      case 5014: error_string="File must be opened with FILE_CSV flag";                                                         break;
      case 5015: error_string="File read error";                                                                                break;
      case 5016: error_string="File write error";                                                                               break;
      case 5017: error_string="String size must be specified for binary file";                                                  break;
      case 5018: error_string="Incompatible file (for string arrays-TXT, for others-BIN)";                                      break;
      case 5019: error_string="File is directory not file";                                                                     break;
      case 5020: error_string="File does not exist";                                                                            break;
      case 5021: error_string="File cannot be rewritten";                                                                       break;
      case 5022: error_string="Wrong directory name";                                                                           break;
      case 5023: error_string="Directory does not exist";                                                                       break;
      case 5024: error_string="Specified file is not directory";                                                                break;
      case 5025: error_string="Cannot delete directory";                                                                        break;
      case 5026: error_string="Cannot clean directory";                                                                         break;
      case 5027: error_string="Array resize error";                                                                             break;
      case 5028: error_string="String resize error";                                                                            break;
      case 5029: error_string="Structure contains strings or dynamic arrays";                                                   break;
      case 5200: error_string="Invalid URL";                                                                                    break;
      case 5201: error_string="Failed to connect to specified URL";                                                             break;
      case 5202: error_string="Timeout exceeded";                                                                               break;
      case 5203: error_string="HTTP request failed";                                                                            break;
      default:   error_string="Unknown Error";
     }
//----
   return(error_string);
  }
//+------------------------------------------------------------------+