Insert null value in DateTime column in ASP.Net using C# and VB.Net

Hi alex0230,

Refer below code

Code

C#

protected void InsertDetails(object sender, EventArgs e)
{
    string constr = ConfigurationManager.ConnectionStrings("constr").ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("Insert into tblWorkOrderSystemAdmin (Date) VALUES (@Date)"))
        {
            cmd.Connection = con;
            if (!string.IsNullOrEmpty(txtScheduledDateForWork.Text.Trim()))
            {
                cmd.Parameters.AddWithValue("@Date", Convert.ToDateTime(txtScheduledDateForWork.Text.Trim()));
            }
            else
            {
                cmd.Parameters.AddWithValue("@Date", DBNull.Value);
            }
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }
}

VB.Net

Protected Sub InsertDetails(ByVal sender As Object, ByVal e As EventArgs)
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("Insert into tblWorkOrderSystemAdmin (Date) VALUES (@Date)")
            cmd.Connection = con
            If Not String.IsNullOrEmpty(txtScheduledDateForWork.Text.Trim()) Then
                cmd.Parameters.AddWithValue("@Date", Convert.ToDateTime(txtScheduledDateForWork.Text.Trim()))
            Else
                cmd.Parameters.AddWithValue("@Date", DBNull.Value)
            End If
            con.Open()
            cmd.ExecuteNonQuery()
            con.Close()
        End Using
    End Using
End Sub