如何解决Linq-包含DateTime字段的动态查询
我进行了如下搜索:
我通过以下代码创建查询:
StringBuilder query = new StringBuilder();
string OrderBy = null;
switch (sortOrder)
{
case "orderCode_desc":
OrderBy = " OrderCode desc";
break;
case "mobile":
OrderBy = "Mobile";
break;
case "mobile_desc":
OrderBy = "Mobile desc";
break;
case "date":
OrderBy = "OrderDate";
break;
case "date_desc":
OrderBy = "OrderDate desc";
break;
case "orderCode":
default:
OrderBy = "OrderCode";
break;
}
if (filters.SelectedProducts.NotNullString())
{
var SelectedProducts = filters.SelectedProducts.Split(',');
query.Append("(");
for (int i = 0; i < SelectedProducts.Length; i++)
{
query.AppendFormat("uag.oag.ordDet.ProductID == {0}",SelectedProducts[i]);
if (i != SelectedProducts.Length - 1)
{
query.Append(" || ");
}
}
query.Append(") && ");
}
if (filters.DateFrom != null && filters.DateTo != null)
{
query.AppendFormat("(uag.oag._order.order.OrderDate >= {0} && uag.oag._order.order.OrderDate <= {1} )",filters.DateFrom.Date,filters.DateTo.Date);
}
if (filters.DateFrom != null && filters.DateTo == null)
{
query.AppendFormat("( uag.oag._order.order.OrderDate >= {0} )",filters.DateFrom.Date);
}
if (filters.DateFrom == null && filters.DateTo != null)
{
query.AppendFormat("( uag.oag._order.order.OrderDate <= {0} )",filters.DateTo.Date);
}
string _query = query.ToString();
_query = _query.EndsWith("&& ") ? _query.Remove(_query.Length - 3) : _query;
orders = db.orders
.Join(db.order_statuses,order => order.OrderStatusID,OrderStatus => OrderStatus.OrderStatusID,(order,OrderStatus) => new { order,OrderStatus })
.Join(db.order_details,_order => _order.order.OrderID,ordDet => ordDet.OrderID,(_order,ordDet) => new { _order,ordDet })
.Join(db.agents_info,oag => oag._order.order.AgentID,ag => ag.AgentInfoID,(oag,ag) => new { oag,ag })
.Join(db.users,uag => uag.ag.UserID,u => u.UserID,(uag,u) => new { uag,u })
.AsQueryable()
.Where(_query)
.Select(m => new OrderList
{
OrderID = m.uag.oag._order.order.OrderID,OrderCode = m.uag.oag._order.order.OrderCode,OrderDate = m.uag.oag._order.order.OrderDate,OrderStatus = m.uag.oag._order.OrderStatus.OrderStatusTitle,TotalPrice = m.uag.oag._order.order.TotalPrice,Mobile = m.u.Mobile
}).OrderBy(OrderBy).Skip(PageSize * (page - 1)).Take(PageSize).ToList();
我得到一个错误:
运算符'> ='与操作数类型'DateTime'和'Int32'不兼容
here是相同的问题,他的问题通过使用参数化查询得以解决。我使用了参数化查询,但问题仍未解决。 我该如何解决这个问题?
解决方法
对于documentation,您需要使用公共构造函数来创建DateTime
对象,因此类似
query.AppendFormat("(uag.oag._order.order.OrderDate >= {0} && uag.oag._order.order.OrderDate <= {1})",filters.DateFrom.Date.ToString(@"Da\teTi\me(yyyy,M,d)"),filters.DateTo.Date.ToString(@"Da\teTi\me(yyyy,d)"));
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。