using System;

using System.Linq;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        var sql = @"

exec sp_executesql N'SELECT 

[Extent1].[ProductName] AS [ProductName]

FROM  [dbo].[Products] AS [Extent1]

INNER JOIN [dbo].[Categories] AS [Extent2] ON [Extent1].[CategoryID] = [Extent2].[CategoryID]

WHERE ([Extent1].[UnitPrice] > @p__linq__0) AND ([Extent2].[CategoryName] = @p__linq__1) AND (N''Chang'' <> [Extent1].[ProductName])',N'@p__linq__0 decimal(1,0),@p__linq__1 nvarchar(4000)',@p__linq__0=1,@p__linq__1=N'Beverages'

";

        Console.WriteLine(ConvertSql(sql));

    }

​

    public static string ConvertSql(string origSql)

    {

        var re = new Regex(@"exec*\s*sp_executesql\s+N'([\s\S]*)',\s*N'(@[\s\S]*?)',\s*([\s\S]*)", RegexOptions.IgnoreCase); // 1: the sql, 2: the declare, 3: the setting

        var match = re.Match(origSql);

        if (match.Success)

        {

            var sql = match.Groups[1].Value.Replace("''", "'");

            //var declare = match.Groups[2].Value;

            var setting = match.Groups[3].Value + ',';

            // to deal with comma or single quote in variable values, we can use the variable name to split

            var re2 = new Regex(@"@[^',]*?\s*=");

            var variables = re2.Matches(setting).Cast<Match>().Select(m => m.Value).ToArray();

            var values = re2.Split(setting).Where(s=>!string.IsNullOrWhiteSpace(s)).Select(m => m.Trim(',').Trim().Trim(';')).ToArray();

            for (int i = variables.Length-1; i>=0; i--)

            {

                sql = Regex.Replace(sql, "(" + variables[i].Replace("=", "")+")", values[i], RegexOptions.Singleline);

            }

            return sql;

        }

        return @"Unknown sql query format.";

​

    }

}