Not able to update database datetime null column value with datepicker null value in c# [duplicate]

I am updating DataTime? column value to null in the database using the Stored procedure and able to update null value in SQL using the same stored procedure. I am using the below code in C#:

if(string.isnullorempty(name)) { name= null; } SqlCommand cmd = new SqlCommand(); cmd = new SqlCommand("procsavedata", conn); cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.AddWithValue("@UserID", UserId); cmd.Parameters.AddWithValue("@Created", (datePicker1.Text.Trim() == string.Empty) ? (DateTime?)null : datePicker1.Value.Date); cmd.Parameters.AddWithValue("@CreatedBy", name); try { conn.Open(); cmd.ExecuteNonQuery(); conn.Close(); } catch { } 

I am able to update the value if datepicker1 and name values exist but if datepicker or name value is null then it is not updating the value in database.