EA programming tutorial Daquan common functions

For each executed MQL4 program, a certain number of variable settings can easily respond to the price state in the chart.

Expert Advisors, scripts or client indicators.

The data is applied to a variable model.

It can be handled separately by predefined variables.

This data is updated by applying the RefreshRates () function after it is turned on.

Ask

Bars

Bid

Close

Digits

High

Low

Open

Point

Time

Volume

Ask

double Ask

The latest selling price for the current currency pair. Use the RefreshRates () function to update.

See MarketInfo ().

Example:

if(iRSI(NULL,0,14,PRICE_CLOSE,0)<25)

{

OrderSend(Symbol(),OP_BUY,Lots,Ask,3,Bid-StopLoss*Point,Ask+TakeProfit*Point,

"My order #2",3,D'2005.10.10 12:30',Red);

return;

}

Bars

int Bars

Returns the number of bars in the chart.

See iBars ().

Example:

int counter=1;

for(int i=1; i<=Bars; i++)

{

Print (close [i-1]);

}

Bid

double Bid

The latest buy price for the current currency pair. Use the RefreshRates () function to update.

See MarketInfo ().

Example:

if(iRSI(NULL,0,14,PRICE_CLOSE,0)75)

{

OrderSend("EURUSD",OP_SELL,Lots,Bid,3,Ask+StopLoss*Point,Bid-TakeProfit*Point,

"My Order #2",3,D'2005.10.10 12:30',Red);

return(0);

}

Close

double Close[]

The series array contains the closing price of each bar on the current chart.

The array elements of the series are ordered in reverse order, i.e. from last to first. The current last bar in the array has an index of 0. The index of the first bar in the chart is Bars-1.

See iClose ().

Example:

int handle = FileOpen("file.csv", FILE_CSV|FILE_WRITE, ";");

if(handle0)

{

//table column title record

FileWrite(handle, "Time;Open;High;Low;Close;Volume");

//data logging

for(int i=0; i

FileWrite(handle, Time, Open, High, Low, Close, Volume);

FileClose(handle);

}

Digits

int Digits

Returns the exchange rate of the current currency pair to decimal places

See MarketInfo ().

Example:

Print (DoubleToStr (Close [0], decimal place));

High

double High[]

The series array contains the highest price for each bar on the current chart.

The array elements of the series are ordered in reverse order, i.e. from last to first. The current last bar in the array has an index of 0. The index of the first bar in the chart is Bars-1.

See iHigh ().

Example:

//---- maximum

i=Bars-KPeriod;

if(counted_barsKPeriod) i=Bars-counted_bars-1;

while(i=0)

{

double max=-1000000;

k = i + KPeriod-1;

while(k=i)

{

price=High[k];

if(max

k--;

}

HighesBuffer=max;

i--;

}

//----

Low

double Low[]

The series array contains the lowest price for each bar on the current chart.

The array elements of the series are ordered in reverse order, i.e. from last to first. The current last bar in the array has an index of 0. The index of the first bar in the chart is Bars-1.

See iLow ().

Example:

//---- minimum

i=Bars-KPeriod;

if(counted_barsKPeriod) i=Bars-counted_bars-1;

while(i=0)

{

double min=1000000;

k = i + KPeriod-1;

while(k=i)

{

price=Low[k];

if(minprice) min=price;

k--;

}

LowesBuffer=min;

i--;

}

//----

Open

double Open[]

The series array contains the opening price of each bar on the current chart.

The array elements of the series are ordered in reverse order, i.e. from last to first. The current last bar in the array has an index of 0. The index of the first bar in the chart is Bars-1.

See iOpen ().

Example:

i = Bars - counted_bars - 1;

while(i=0)

{

double high = High;

double low = Low;

double open = Open;

double close = Close;

AccumulationBuffer = (close-low) - (high-close);

if(AccumulationBuffer != 0)

{

double diff = high - low;

if(0==diff)

AccumulationBuffer = 0;

else

{

AccumulationBuffer /= diff;

AccumulationBuffer *= Volume;

}

}

if(i

i--;

}

double Point

Returns the point value of the current chart

See MarketInfo ().

Example:

OrderSend(Symbol(),OP_BUY,Lots,Ask,3,0,Ask+TakeProfit*Point);

datetime Time

datetime Time[]

The series array contains the opening time of each bar for the current chart. The data is presented as datetime, in seconds from 0:00 on January 1, 1979.

The array elements of the series are ordered in reverse order, that is, from the last to the first. The current last bar has an index of 0 in the array. The index of the first bar in the chart is Bars-1.

See iTime ().

Example:

for(i=Bars-2; i=0; i--)

{

if(High[i+1] LastHigh) LastHigh = High[i+1];

if(Low[i+1] < LastLow) LastLow = Low[i+1];

//----

if(TimeDay(Time) != TimeDay(Time[i+1]))

{

P = (LastHigh + LastLow + Close[i+1])/3;

R1 = P*2 - LastLow;

S1 = P*2 - LastHigh;

R2 = P + LastHigh - LastLow;

S2 = P - (LastHigh - LastLow);

R3 = P*2 + LastHigh - LastLow*2;

S3 = P*2 - (LastHigh*2 - LastLow);

LastLow = Open;

LastHigh = Open;

}

//----

PBuffer = P;

S1Buffer = S1;

R1Buffer = R1;

S2Buffer = S2;

R2Buffer = R2;

S3Buffer = S3;

R3Buffer = R3;

}

Volume

double Volume[]

The series array contains the volume of each column of the current chart.

The array elements of the series are ordered in reverse order, i.e. from last to first. The current last bar in the array has an index of 0. The index of the first bar in the chart is Bars-1.

See iVolume ().

Example:

if(i==0 && time0

{

d_volume += Volume[0];

if(Low[0]

if(High[0]d_high) d_high = High[0];

d_close = Close[0];

}

last_fpos = FileTell(ExtHandle);

last_volume = Volume;

FileWriteInteger(ExtHandle, i_time, LONG_VALUE);

FileWriteDouble(ExtHandle, d_open, DOUBLE_VALUE);

FileWriteDouble(ExtHandle, d_low, DOUBLE_VALUE);

FileWriteDouble(ExtHandle, d_high, DOUBLE_VALUE);

FileWriteDouble(ExtHandle, d_close, DOUBLE_VALUE);

FileWriteDouble(ExtHandle, d_volume, DOUBLE_VALUE);