Jint .net平台的javascript引擎

使用需求

有时候一段Javascript代码写的很棒,而我们又无法将之翻译成.net或翻译之成本很高的时候

我们就可以使用Jint引擎来运行Javascript代码,来得到我们想要的结果

或者上

http://jint.codeplex.com/releases/view/119215

下面代码使用的 0.9.2.0 版本

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using Jint;

namespace JIntTest
{
    /// <summary>
    /// 这里一这要是 public,否则JInt无法反射
    /// </summary>
   public  class Student
    {
        public string Id { get; set; }
        public string Name { get; set; }
    }
    class Program
    {
        static void Main(string[] args)
        {

            //简单判断
            var b = JavascriptUtil.Execute<int>("1>0", null);
            //直接给参数赋值

　　　　　　　string str = "var stu={};stu.Id=Id;stu.Name=Name; return stu.Id";

            Dictionary<string, object> dict = new Dictionary<string, object>();

            dict.Add("Id", "001");
            dict.Add("Name", "Aven");
            var c = JavascriptUtil.Execute<string>(str, dict);

            //通过类实例来赋值
            Dictionary<string, object> dict2 = new Dictionary<string, object>();
            var st = new Student//这里一定要使用public
            {
                Id = "002",
                Name = "Grace"
            };
            dict2.Add("ST",st);
            var str2 = "var stu={};stu.Id=ST.Id;stu.Name=ST.Name; return stu.Id";
            var d = JavascriptUtil.Execute<string>(str2, dict2);

        }

        public static string ReadFile(string path)
        {
            StreamReader sr = new StreamReader(path, Encoding.Default);
            String line;
            StringBuilder sb = new StringBuilder();
            while ((line = sr.ReadLine()) != null)
            {
                sb.AppendLine(line);

            }
            return sb.ToString();

        }

    }
    public static class JavascriptUtil
    {

        static JavascriptUtil()
        {

        }

        public static object Execute<T>(string expression, Dictionary<string, object> args)
        {

            if (string.IsNullOrEmpty(expression))
            {
                if (typeof(T) == typeof(int) || typeof(T) == typeof(decimal) || typeof(T) == typeof(double) || typeof(T) == typeof(float))

                {
                    return 0;
                }

                if (typeof(T) == typeof(DateTime))
                {
                    return DateTime.MinValue;
                }

                if (typeof(T) == typeof(string))
                {
                    return "";
                }

                return default(T);
            }

            if(typeof(T)==typeof(int))
            {
                var result = JintExecute(expression, args);
                return Convert.ToInt32(result);
            }
            if (typeof(T) == typeof(decimal ))

            {
                var result = JintExecute(expression, args);
                return Convert.ToDecimal(result);
            }
            if (typeof(T) == typeof(double ))

            {
                var result = JintExecute(expression, args);
                return Convert.ToDouble(result);
            }
            if (typeof(T) == typeof(DateTime ))

            {
                var result = JintExecute(expression, args);
                return Convert.ToDateTime(result);
            }

            return JintExecute(expression, args);
        }

        public static object JintExecute(string expression, Dictionary<string, object> args)
        {
            var engine = _engine;

            if (args != null)
            {
                foreach (var x in args)
                {
                    engine.SetParameter(x.Key, x.Value);
                }
            }
            return engine.Run(expression) ;
        }

        private static JintEngine _engine= new JintEngine();

    }
}