You can get yesterday and today using DateTime add days method. Here we will see how to get today and yesterday's date in [C#.net] and [Vb.net].

Program to get yesterday in [C#].

using System;
namespace DateAndTime.Examples
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Today is {0}", DateTime.Today);
DateTime yesterday  = GetYesterdayDate();
Console.WriteLine("Yesterday is: {0}", yesterday);
Console.ReadLine();
}
static DateTime GetYesterdayDate()
{      
return DateTime.Today.AddDays(-1);
}
}
}

(VB.net) example to get yesterdays day.

Namespace DateAndTime.Examples
Class Program
Private Shared Sub Main(args As String())
Console.WriteLine("Today is {0}", DateTime.Today)
Dim yesterday As DateTime = GetYesterdayDate()
Console.WriteLine("Yesterday is: {0}", yesterday)
Console.ReadLine()
End Sub
Private Shared Function GetYesterdayDate() As DateTime
Return DateTime.Today.AddDays(-1)
End Function
End Class
End Namespace

Today is 1/1/2012 12:00:00 AM.
Yesterday is: 12/31/2011 12:00:00 AM.

Example shows today and yesterdays date and time. DateTime.Today gives today's date. GetYesterdayDate() function returns yesterdays date. AddDays method accepts number of day's to add in given date.

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