C# Linq - 从 DateTime 中选择日期
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Linq - Select Date from DateTime
提问by RealSteel
I have a LinqResult from which I need to select only Datefrom DateTime.
My Query goes like this :
我有一个Linq结果，我只需Date要从DateTime.
我的查询是这样的：
var UserTemplates = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1
select new
{
xx.TEMPLATE_ID,
xx.TEMPLATE_NAME,
//CREATED_DATE = xx.CREATED_DATE.Value.Date
//CREATED_DATE = EntityFunctions.TruncateTime(xx.CREATED_DATE)
xx.CREATED_DATE
}).ToList();
Is that Possible? Any help would be greatly appreciated.
那可能吗？任何帮助将不胜感激。
CREATED_DATE - `datetime` datatype
Actually,I'm Binding it to a Control as a DataSourceand the control is displaying both Date and Time.But I want to display only date.
实际上，我将它作为 a 绑定到一个控件，DataSource并且该控件同时显示Date and Time. 但我只想显示date.
When I'm trying with CREATED_DATE = xx.CREATED_DATE.Value.Date,It is giving an error like :
当我尝试使用时CREATED_DATE = xx.CREATED_DATE.Value.Date，它给出了如下错误：
The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.
LINQ to Entities 不支持指定的类型成员“日期”。仅支持初始值设定项、实体成员和实体导航属性。
采纳答案by Kaf
If it is for presentation purpose, then you can use DataFormatStringproperty. For Example, if you are binding a datasource to a GridView, you could do as;
如果是为了演示目的，那么您可以使用DataFormatString属性。例如，如果您将数据源绑定到 GridView，您可以这样做；
<asp:BoundField DataField="CREATED_DATE" ...
DataFormatString="{0:d}" ../>
Else you can use EntityFunctions.TruncateTime()which returns the input date without the time portion.
否则，您可以使用EntityFunctions.TruncateTime()返回没有时间部分的输入日期。
EntityFunctions.TruncateTime(xx.CREATED_DATE)
Your query would be like;
您的查询将是这样的；
var UserTemplates = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1
select new
{
xx.TEMPLATE_ID,
xx.TEMPLATE_NAME,
EntityFunctions.TruncateTime(xx.CREATED_DATE) //new like
}).ToList();
回答by Dbuggy
Perhaps this ?
也许这个？
var qry = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1
select new { xx.TEMPLATE_ID, xx.TEMPLATE_NAME, xx.xx.CREATED_DATE });
var UserTemplates = qry.AsEnumerable().Select(xx => new
{
xx.TEMPLATE_ID,
xx.TEMPLATE_NAME,
xx.CREATED_DATE.Value.Date
}).ToList();
回答by Damith
var UserTemplates = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1 select xx).AsEnumerable()
.Select( i=> new
{
i.TEMPLATE_ID,
i.TEMPLATE_NAME,
CREATED_DATE = i.CREATED_DATE.ToString("M/d/yyyy"),
i.CREATED_DATE
}).ToList();
回答by Dharmendra Prajapati
Use this...It worked for me..
使用这个......它对我有用..
var UserTemplates = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1
select new
{
xx.TEMPLATE_ID,
xx.TEMPLATE_NAME,
CREATED_DATE=SqlFunctions.DateName("day", xx.CREATED_DATE).Trim() + "/" +
SqlFunctions.StringConvert((double)xx.CREATED_DATE.Value.Month).TrimStart() + "/" +
SqlFunctions.DateName("year", xx.CREATED_DATE)
}).ToList();
And Output Date will be dd/MM/yyyy format
并且输出日期将为 dd/MM/yyyy 格式
回答by Karthic G
Try this,
尝试这个，
var UserTemplates = (from xx in VDC.SURVEY_TEMPLATE
where xx.USER_ID == userid && xx.IS_ACTIVE == 1
select new Attributes
{
TEMPLATE_ID=xx.TEMPLATE_ID,
TEMPLATE_NAME=xx.TEMPLATE_NAME,
dateCreatd = xx.CREATED_DATE
})
.AsEnumerable()
.select(p=>new Attributes
{
TEMPLATE_ID =p.TEMPLATE_ID,
TEMPLATE_NAME=p.TEMPLATE_NAME,
dateString = p.dateCreatd .Value.toString("YYYY-MMM-dd")
}).ToList();
public class Attributes
{
public string TEMPLATE_ID { get; set; }
public string TEMPLATE_NAME { get; set }
public DateTime dateCreatd { get; set; }
public string dateString { get; set; }
}
hopes it is useful to you
希望对你有用
