It seems that the Standard date and time string matches your desired format, so you need to build a Custom date and time format string
This should do the trick:
string.Format("{0:MMMM dd, yyyy}", value)
Or alternatively
value.ToString("MMMM dd, yyyy")
- MMMM is the full name of the month, for example. June (en-US)
- dd - Day of the month, from 01 to 31
- yyyy - year as a four-digit number.
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