public static bool DeleteMessages(this SupportContext context, out int rowscount)
{
try
{
rowscount = context.Database
.ExecuteSqlCommand("DELETE FROM [support].[dbo].[message]");
var r = context.Database // using T-SQL instead of recreating the table as there is no alternative in EF for reseed
.ExecuteSqlCommand("DBCC CHECKIDENT ('[support].[dbo].[message]', RESEED, 0)");
return(true);
}
catch (Exception ex)
{
rowscount = 0;
return(false);
}
}
/// <summary>
/// Complex async method for both emloyees and clients. Contains another check wether login belongs to
/// employee.
/// </summary>
/// <param name="login">login</param>
/// <param name="num">time offset for employee, id for client</param>
/// <returns></returns>
public static async Task <Message> MessageAsync(this SupportContext context, string login, int num)
{
Message message = null; // using null assignment while object? still unavailable
if (await context.Employees.AnyAsync(p => p.Login == login)) // num as time offset if employee
{
var messages = context.Messages // unfinished messages for current employee first
.Where(p => p.OperatorId == login && p.Finished == null)
.ToArray();
if (messages.Length > 0)
{
message = messages.OrderBy(p => p.Id).First();
}
else
{
var created = DateTime.Now.AddSeconds(-num);
messages = context.Messages // messages suitable with time offset
.Where(p => p.OperatorId == null && p.Finished == null && p.Created < created)
.ToArray();
if (messages.Length > 0)
{
message = messages.OrderBy(p => p.Id).First();
}
}
}
else // num as id if client
{
var m = await context.Messages.FindAsync(num);
if (m.Client == login) // additional ownership check
{
message = m;
}
}
return(message);
}
