将PHP脚本转换为C＃

I am currently stuck right now. I have moved to C# but one of the scripts in my PHP won't work when i convert it to C#. I have some problems with the array of minutes. Here is my PHP Script:

<?php
$start_hour = 10;
$end_hour = 22;
$minutes_array = array("15", "30", "45");
for($i=$start_hour; $i<($end_hour + 1); $i++){
    $string = $i . ':00';
    echo '<option value="' . $string . '">' . $string . '</option>';
    if($i != $end_hour){
        for($j=0; $j<sizeof($minutes_array); $j++){
            $string = $i . ':' . $minutes_array[$j];
             echo '<option value="' . $string . '">' . $string . '</option>';
        }
    }
}
?>

What it does is it outputs list items from 10 to 22 with 15, 30 and 45 between every count. So it looks like this

DropdownList
10:00
10:15
10:30
10:45
11:00
11:15
etc..

And here is my C# code so far:

int Opened = 8;
    int Closed = 22;

    for (int i = Opened; i < (Closed); i++)
    {
        string String = i + ":00";
        Response.Write(String);
        if (i != Closed)
        {
            for(int j = 0; j<sizeof(); j++)
            {
                String = i + ":" + 
            }
        }
    }

Can anyone help me converting this to C#? It would really make my day!

Thanks in advance, Jens

var startHour = new DateTime(2000, 01, 01, 08, 00, 00);
var endHour = new DateTime(2000, 01, 01, 22, 00, 00);
var step = TimeSpan.FromMinutes(15);
for (var time = startHour; time <= endHour; time += step)
{
    Console.WriteLine(time.ToString("HH:mm"));
}

in php you are doing the following code for($i=$start_hour; $i<($end_hour + 1); $i++){ While in c# you are not adding the value. for (int i = Opened; i < (Closed); i++)

using datetime variables

        var open = 8;
        var close = 22;

        var c = new DateTime(2014, 1, 1, open, 0, 0);
        var d = new DateTime(2014, 1, 1, close, 0, 0); ;

        while (c < d)
        {
            Console.WriteLine(string.Format("{0}:{1}", c.ToString("hh"), c.ToString("mm")));
            c = c.AddMinutes(15);
        }

The below code will do what you need:

List<string> Time = new List<string>();

int hourStart = 8;
int hourFinish = 22;

for (int h = hourStart; h <= hourFinish; h++)
{
    for (int m = 0; m < 60; m = m + 15)
    {
        string hours;
        string minutes;

        // this section is used to format the 0 to 00
        if (h == 0)
            hours = "00";
        else
            hours = h.ToString();

        if (m == 0)
            minutes = "00";
        else
            minutes = m.ToString();

        string time = hours + ":" + minutes;

        Time.Add(time);
    }
}