using System.Linq.Dynamic.Core;

using System.Collections.Generic;

using System.Text;

using System.Text.RegularExpressions;

using System;

using System.Linq;

​

TestDyamicSqlEvaluation(

    "{@Param1} = \"TEST\"", 

    new Dictionary<string, object> { { "Param1", "TEST" } }, 

    true);

​

TestDyamicSqlEvaluation(

    "2 > 1",

    new Dictionary<string, object> { { "Param1", "TEST" } },

    true);

​

TestDyamicSqlEvaluation(

    "2 < 1",

    new Dictionary<string, object> { { "Param1", "TEST" } },

    false);

​

TestDyamicSqlEvaluation(

    "{@Param1} != \"TEST\" && {@Param2} = 2 && {@Param1} != \"TEST1\"", 

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 2 } }, 

    true);

​

TestDyamicSqlEvaluation(

    "{@Param1} != \"TEST\" && {@Param2} = 3 && {@Param1} != \"TEST1\"",

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 3 } },

    true);

​

TestDyamicSqlEvaluation(

    "{@Param1} != \"TEST\" && {@Param2} = 2 && {@Param1} != \"TEST1\"",

    new Dictionary<string, object> { { "Param1", "TEST" }, { "Param2", 3 } },

    false);

​

TestDyamicSqlEvaluation(

    "{@Param1} = \"TEST\" || 2 > 1",

    new Dictionary<string, object> { { "Param1", "TEST2" } }, 

    true);

​

TestDyamicSqlEvaluation(

    "{@Param2} < 1 || {@Param1} = \"TEST\"",

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 2 } },

    false);

​

TestDyamicSqlEvaluation(

    "{@Param2} < 1 || {@Param1} = \"TEST\"",

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 0.2f } },

    true);

​

TestDyamicSqlEvaluation(

    "{@Param1}.Contains(\"ES\")",

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 0.2f } },

    true);

​

TestDyamicSqlEvaluation(

    "{@Param1}.Contains(\"ESS\")",

    new Dictionary<string, object> { { "Param1", "TEST2" }, { "Param2", 0.2f } },

    false);

​

Console.ReadKey();

return;

​

void TestDyamicSqlEvaluation(string condition, Dictionary<string, object> parameters, bool expectedResult)

{

    var result = DyamicSqlEvaluation(condition, parameters);

    Console.WriteLine("{0} EXPECTED={1} ACTUAL={2} WORKED={3}", condition, expectedResult, result, expectedResult == result);

}

​

bool DyamicSqlEvaluation(string conditionWithParameterSyntax, Dictionary<string, object> parameters)

{

    var dynamicWhereClause = GetDynamicWhereClause(conditionWithParameterSyntax, parameters);

​

    return new List<int> { 1 }.AsQueryable().Any(dynamicWhereClause.condition, dynamicWhereClause.parameters);

}

​

(string condition, object[] parameters) GetDynamicWhereClause(string conditionWithParameterSyntax, Dictionary<string, object> parameters)

{

    var replacements = new Dictionary<string, string>();

    var whereClauseParameters = new List<object>();

​

    var matches = Regex.Matches(conditionWithParameterSyntax, @"\{\s*@\s*(\w+)\s*\}");

​

    int i = 0;

​

    foreach (var match in matches)

    {

        var key = ((Match)match).Groups[1].Value;

​

        if (!replacements.ContainsKey(key))

        {

            replacements[key] = $"@{i}";

            i++;

​

            whereClauseParameters.Add(parameters[key]);

        }

    }

​

    var condition = new StringBuilder(conditionWithParameterSyntax);

    foreach (var replacement in replacements)

    {

        condition = condition.Replace($"{{@{replacement.Key}}}", replacement.Value);

    }

​

    return (condition.ToString(), whereClauseParameters.ToArray());

}

​