{MQL4) How to know OrdersTotal() is decreased. - page 2

[Fernando Carreiro]

kajironpu:

Fernando san  Obrigado!

WRONG_VALUE is first time to see. Is it kind of EMPTY_VALUE?

I will study your code deeply...

You are welcome!

They are all constants and EMPTY_VALUE is more useful for indicator buffers as its value is (2147483647), while EMPTY and WRONG_VALUE  both have a value of (-1).

However, I prefer using WRONG_VALUE (instead of EMPTY) because it can also be used with enumerations as it is implicitly cast.

EMPTY, WRONG_VALUE, INVALID_HANDLE, CLR_NONE, clrNONE are constants that return the value (-1), so when in doubt, always read the documentation (either online or by simply hitting F1 in MetaEditor).

• https://docs.mql4.com/constants/namedconstants/otherconstants

[hock]

kajironpu:

Hi,I want to know how to code the OrdersTotal() is changed(decreased).

For example, I have 5 orders now. OrdersTotal()=5.

If one order is closed (either TP or SL)  and OrdersTotal() is now 4 orders, The number of order was  decreased.

How can I know this?

Hi, nice to meet you all.

I have quection how to increased the order???
EX: this EA only open 1 trade, but i want to open more trades (3 orders) at same time.

extern double Lots = 0.01;

extern int StopLoss = 300;

extern int TakeProfit = 50;

int g_bars_92;

bool gi_96 = TRUE;

int init() {

   if (Digits == 3 || Digits == 5) {

      StopLoss = StopLoss;

      TakeProfit = TakeProfit;

   }

   return (0);

}

int deinit() {

   return (0);

}

int start() {

   if (g_bars_92 < Bars && TOOC() == 0 && g_bars_92 != 0 && gi_96) OrderSend(Symbol(), OP_BUY, Lots, Ask, 0, Bid - StopLoss * Point, Ask + TakeProfit * Point, 0, 0, 0, Red);

   g_bars_92 = Bars;

   if (TOOC() == 1) gi_96 = FALSE;

   Comment("Error: ", GetLastError());

   return (0);

}

int TOOC() {

   int li_ret_0;

   for (int l_pos_4 = 0; l_pos_4 < OrdersTotal(); l_pos_4++) {

      if (OrderSelect(l_pos_4, SELECT_BY_POS, MODE_TRADES))

         if (OrderSymbol() == Symbol()) li_ret_0++;

   }

   return (li_ret_0);}

}

[nicholish en]

Fernando Carreiro:

You are welcome!

They are all constants and EMPTY_VALUE is more useful for indicator buffers as its value is (2147483647), while EMPTY and WRONG_VALUE  both have a value of (-1).

However, I prefer using WRONG_VALUE (instead of EMPTY) because it can also be used with enumerations as it is implicitly cast.

EMPTY, WRONG_VALUE, INVALID_HANDLE, CLR_NONE, clrNONE are constants that return the value (-1), so when in doubt, always read the documentation (either online or by simply hitting F1 in MetaEditor).

• https://docs.mql4.com/constants/namedconstants/otherconstants

Additionally, WRONG_VALUE is A value; WRONG. The same also goes for NULL. With certain types, NULL isn't really null but it's a zero value, and can mess you up if you are coming from another language where null really is a sentinel value. 

int x = NULL;
Print(x == 0); //true

These two value constants can be useful for checking enums and some MQL function returns for return errors, however, they should never be used in a place where a sentinel value is required. A sentinel value indicates that the variable has NOT been set and has "None" or "null" value. It is unfortunate that MQL doesn't have a universal sentinel value that evaluates in the implicit way that WRONG_VALUE does. I have found a solution to this problem, however, and you can install my None type library which will then allow you to use safe and unambiguous sentinel values for all types.

https://www.mql5.com/en/forum/285144/page9#comment_9176346