feat：查询所有挂单

@@ -94,6 +94,13 @@ class BinanceFutures
         return $this->requestAccount($method, $path, $param);
     }
 
+    //查询所有挂单
+    public function openOrders($param)
+    {
+        $path   = '/fapi/v1/openOrders';
+        $method = 'GET';
+        return $this->requestAccount($method, $path, $param);
+    }
     //取消所有订单
     public function cancelAllOpenOrders($param)
     {