1.Get current date
DateTime today = DateTime.Today;var today = DateTime.Now;
var tomorrow = today.AddDays(1);
var yesterday = today.AddDays(-1);2.datetimeto string
@item.WorkDate.Value.ToString("yyyy-MM-dd")
3.timespan to string
timespan.ToString("hh':'mm':'ss");
or
timespan.ToString(@"hh\:mm");
4.Entity Framework: adding existing child POCO to new Parent POCO, creates new child in DB
https://stackoverflow.com/questions/14307838/entity-framework-adding-existing-child-poco-to-new-parent-poco-creates-new-chi
Approach 1 - Setting Entity State
using (var context = new Context())
{
var book = new Book();
book.Name = "Service Design Patterns";
book.Publisher = new Publisher() {Id = 2 }; // Only ID is required
context.Entry(book.Publisher).State = EntityState.Unchanged;
context.Books.Add(book);
context.SaveChanges();
}Approach 2 - Using Attach method
using (var context = new Context())
{
var book = new Book();
book.Name = "Service Design Patterns";
book.Publisher = new Publisher() { Id = 2 }; // Only ID is required
context.Publishers.Attach(book.Publisher);
context.Books.Add(book);
context.SaveChanges();
}
程式記記 (4)
