Question

This code is a simplified version of what I’m trying to do:

string day = Thursday;
DateTime dt = DateTime.Now;

if (day == dt.DayOfWeek)
{
     // start the program
}

I need to read a day of the week value from a database, assign it to a string, then compare the string to dt.DayOfWeek to check if the program should execute.

My error is this: “Operator ‘==’ cannot be applied to operands of type ‘string’ and ‘System.DayOfWeek”

Anyone know how to compare a string to a DateTime.DayOfWeek value?

Answer 1

Easiest is to convert enum to string:

if (day == dt.DayOfWeek.ToString())...

Notes:

• if you can change type of day to DayOfWeek enum you can avoid string comparisons (and its related localization/comparison issues).
• if you have to use string make sure to decide if case is important or not (i.e. should “thursday” be equal to DayOfWeek.Thursday) and use corresponding String.Equals method.
• consider converting string to enum with Parse as suggested in other answers: ((DayOfWeek)Enum.Parse(typeof(DayOfWeek), day)
• make sure incoming string is always English – if it could be in other languages you’ll need to look into manually matching value to one provided in CultureInfo.DateTimeFormat.DayNames.