i have a problem whlile inserting the values(date time, time) into the database from the textbox value .I donot understnd how to convert the data type .Pls help !

var x = DateTime.MinValue;
var b = DateTime.TryParse(txtcaldatetime.Text,out x);

string sql = "insert into Tutor values(@tutorNumber, @studentNumber, @calDateTime, @timeSpent, @notes)";
SqlConnection connection = new SqlConnection(/* connection info */);
SqlCommand command = new SqlCommand(sql, connection);

//Repeat this bit for each parameter you need to pass
command.Parameters.Add(new SqlParameter {
        ParameterName = "@Notes",
        SqlDbType = SqlDbType.NVarChar,
        Direction = ParameterDirection.Input,
        Value = txtNotes.Text,
});

command.ExecuteNonQuery();

Dim sql As String = "insert into Tutor values(@tutorNumber, @studentNumber, @calDateTime, @timeSpent, @notes)"
	' connection info 
Dim connection As New SqlConnection()
Dim command As New SqlCommand(sql, connection)

'Repeat this bit for each parameter you need to pass
command.Parameters.Add(New SqlParameter() With { _
	Key .ParameterName = "@Notes", _
	Key .SqlDbType = SqlDbType.NVarChar, _
	Key .Direction = ParameterDirection.Input, _
	Key .Value = txtNotes.Text _
})

command.ExecuteNonQuery()