C# .NET - How to calculate num of weekdays between 2 dates

Hi everyone,

Sorrry to trouble you all again.

I have 2 dates which I subtract from each other to find out the number of days between them.  

As follows: -

this.txttotdays.Text = (DateTime.Parse(this.txtDate4.Text) - DateTime.Parse(this.txtDate1.Text)).Days.ToString();

Can someone show me how to modify this line of code to get a count of weekdays only

Thanks

DateTime  asof,bday;
TimeSpan span = asof - bday;
Console.Writeline(span.Days());

I used you suggestion is this code: -

TimeSpan span = (DateTime.Parse(this.txtDate4.Text) - DateTime.Parse(this.txtDate1.Text));
this.txtTotDays2.Text = span.Days.ToString();

but got an answer including weekends

Can you help further

You need to itereate over the DateTimes
and find the DayOfWeek of every dateTime. If this is Monday through Friday then Increment your  counter by1.

Below link elaborates this 
http://www.dotnet247.com/247reference/msgs/32/162879.aspx

I saw examples using a loop and counter, but it could cause slow performance in some circumstances, so I set about finding a formula based approach. I was unable to find such a formula after digging deep into Google, so I wrote my own. Let me just say it was a lot more challenging than I thought it would be.

    int Weekdays(DateTime dtmStart, DateTime dtmEnd)
    {
        // This function includes the start and end date in the count if they fall on a weekday
        int dowStart = ((int)dtmStart.DayOfWeek == 0 ? 7 : (int)dtmStart.DayOfWeek);
        int dowEnd = ((int)dtmEnd.DayOfWeek == 0 ? 7 : (int)dtmEnd.DayOfWeek);
        TimeSpan tSpan = dtmEnd - dtmStart;
        if (dowStart <= dowEnd)
        {
            return (((tSpan.Days / 7) * 5) + Math.Max((Math.Min((dowEnd + 1), 6) - dowStart), 0));
        }
        else
        {
            return (((tSpan.Days / 7) * 5) + Math.Min((dowEnd + 6) - Math.Min(dowStart, 6), 5));
        }
    }