c# – 使用当前文化定义的12或24小时格式,从DateTime获取一小时

// displays "15" because my current culture is en-GB
Console.WriteLine(DateTime.Now.ToHourString());

// displays "3 pm"
Console.WriteLine(DateTime.Now.ToHourString(new CultureInfo("en-US")));

// displays "15"
Console.WriteLine(DateTime.Now.ToHourString(new CultureInfo("de-DE")));

// ...

public static class DateTimeExtensions
{
    public static string ToHourString(this DateTime dt)
    {
        return dt.ToHourString(null);
    }

    public static string ToHourString(this DateTime dt,IFormatProvider provider)
    {
        DateTimeFormatInfo dtfi = DateTimeFormatInfo.GetInstance(provider);

        string format = Regex.Replace(dtfi.ShortTimePattern,@"[^hHts]","");
        format = Regex.Replace(format,@"s+"," ").Trim();

        if (format.Length == 0)
            return "";

        if (format.Length == 1)
            format = '%' + format;

        return dt.ToString(format,dtfi);
    }
}