Closing an Order By Opposite

Request: close one open order using another opposite-position order Sends a request to match and close two opposite-direction orders by ticket.

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Code Example

// --- Quick use (service wrapper) ---
await _service.CloseByOrderExample(123456, 654321);

// --- Low-level (direct account call) ---
// Preconditions: account is connected via ConnectByServerName/ConnectByHostPort.
// Both tickets must be OPEN and of OPPOSITE types (Buy vs Sell) on the SAME symbol.

using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));

var request = new OrderCloseByRequest
{
    TicketToClose = 123456,
    OppositeTicketClosingBy = 654321
};

var result = await _mt4.OrderCloseByAsync(
    request: request,
    deadline: null,
    cancellationToken: cts.Token);

Console.WriteLine($"Closed by opposite: Profit={result.Profit}, Price={result.ClosePrice}, Time={result.CloseTime}");

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Method Signatures

// Service wrapper (example implementation)
Task CloseByOrderExample(long ticket, long oppositeTicket);

// Low-level account call
Task<OrderCloseByData> OrderCloseByAsync(
    OrderCloseByRequest request,
    DateTime? deadline = null,
    CancellationToken cancellationToken = default
);

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🔽 Input

• request (OrderCloseByRequest) — structure with:

Field	Type	Description
TicketToClose	int	Ticket ID of the primary order to close.
OppositeTicketClosingBy	int	Ticket ID of the opposite order used to close the first one.

Optional:

• deadline (DateTime?) — optional per-call deadline.
• cancellationToken (CancellationToken) — to cancel the request.

⚠️ Both tickets must be valid open orders, on the same symbol, and with opposite directions.

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⬆️ Output

Returns OrderCloseByData with:

Field	Type	Description
Profit	double	Profit/loss from the close-by operation.
ClosePrice	double	Execution price of the operation.
CloseTime	string	Timestamp of the operation (UTC).

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🎯 Purpose

Close matched hedge positions — one Buy and one Sell — via the Close By mechanism. This can reduce commission/slippage compared to closing each order separately.

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🧩 Notes & Tips

• Same symbol & opposite side. Close By works only when both orders are for the same instrument and have opposite directions.
• Volumes. Brokers commonly require equal volumes for a single Close By operation. If volumes differ, the request may be rejected; use partial close(s) or multiple operations if supported by your workflow.
• Ticket range. This API uses int tickets on the wire. If you store tickets as long, ensure they fit into Int32 before sending.
• Hedging mode. Close By implies hedged positions. If the account/broker enforces netting, this operation may not be allowed.

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⚠️ Pitfalls

• Already closed/invalid ticket. Expect an API error if either ticket is not currently open.
• Different symbols or same side. Any mismatch leads to a clear server error.
• Symbol suffixes. EURUSD.m and EURUSD are different instruments — match exactly.

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🧪 Testing Suggestions

• Happy path. Open a Buy and a Sell with the same symbol and same lot; call OrderCloseByAsync and verify Profit aligns with price difference and contract settings.
• Edge cases. Try mismatched symbols or same-side tickets and confirm a proper ApiExceptionMT4 is thrown and handled.
• Timeouts. Use a short cancellation window (e.g., 3–5s) and verify graceful cancellation without leaving partial states.