check Prime number in .net

Prime Number : If any number is bigger than one and has no divisors other than 1 and itself then this number is called by Prime number. For example 3 is prime, since no number except 1 and 3 divides it. Similarly 6 is not prime because it divide by 2 and 3.

following example show how to check given number is prime or not
[vb.net]

Private Sub CheckPrimeNumber(ByVal number As Integer)
        Dim IsPrime As Boolean = True
        For i = 2 To number / 2
            If (number Mod i = 0) Then
                IsPrime = False
                Exit For
            End If
        Next i
        If IsPrime = False Then
            MsgBox("Number id not Prime")
        Else
            MsgBox("Number is Prime")
        End If
End Sub

[C#]

private void CheckPrimeNumber(int number)
{
	bool IsPrime = true;
	for (i = 2; i <= number / 2; i++) {
		if ((number % i == 0)) {
			IsPrime = false;
			break; 
		}
	}
	if (IsPrime == false) {
		Interaction.MsgBox("Number id not Prime");
	} else {
		Interaction.MsgBox("Number is Prime");
	}
}