using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		var str = @"CREATE TABLE [dbo].[Event](
    [ID] [int] IDENTITY(1,1) NOT NULL,
    [Date Started] [datetime] NOT NULL,
    [StartTime] [time](7) NOT NULL,
    [Description] [nvarchar](250) NULL,
    [AudioLocation] [nvarchar](max) NOT NULL,
    [PlayerLocation] [nvarchar](max) NOT NULL,
 CONSTRAINT [PK_dbo.Event] PRIMARY KEY CLUSTERED";
        var result = Regex.Replace(str, @"\[(\w+)]|\[([^]]+)]", m => m.Groups[1].Success ? m.Groups[1].Value : $"\"{m.Groups[2].Value}\"");
        Console.WriteLine(result);
	}
}