C#运算String型表达式

现在有一个小需求就是一个xml中有一个condition节点，节点中包含有一个字符串类型的表达式，要对这个表达式进行运算，判断运算结果是true还是false。

如下：

　　<Condition Type="CONDITION">param1>3</Condition>

现需要运算condition中的表达式param1>3。表达式的语法符合javascript表达式语法。

 

解决的代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.JScript;

namespace TestXpression
{
class Program
{
/// <summary>
/// 微软提供的运算符合js语法的表达式
/// </summary>
/// <param name="sExpression"></param>
/// <returns></returns>
public static object EvalExpress(string sExpression)
{

Microsoft.JScript.Vsa.VsaEngine ve = Microsoft.JScript.Vsa.VsaEngine.CreateEngine();
return Microsoft.JScript.Eval.JScriptEvaluate(sExpression, ve);
}

/// <summary>
/// 传入参数，将参数和参数值进行拼接
/// </summary>
/// <param name="name"></param>
/// <param name="value"></param>
/// <param name="type"></param>
/// <returns></returns>
public static string trans(string name, string value,string type)
{
string s = "";
//"var a=10;var b=15;var c='hello'"
//string s = "var " + name + "=" + value.ToString() + ";";
if (type == "stringType")
{
s = "var " + name + "=" + "'" + value.ToString() + "'" + ";";
}
else {
s = "var " + name + "=" + value.ToString() + ";";
}
return s;

}


public static string MakeCondition()
{

Dictionary<string, string> myParameters = new Dictionary<string, string>();

myParameters.Add("xingCan1", "15");
myParameters.Add("xingCan2", "10");
myParameters.Add("xingCan3","C");

string condition = "";

string type = "stringType";

foreach (var ss in myParameters)
{
condition += trans(ss.Key.ToString(), ss.Value.ToString(), type);

}
string expression1 = "xingCan1>xingCan2";

string expression2 = "xingCan3=='C'";

// ------------参数赋值--------------------------- <<<<条件>>>>>
//"var xingCan1=10;var xingCan2=15;var xingCan3='C';xingCan3=='C'"
condition += expression1;
return condition;
}

static void Main(string[] args)
{
string s = MakeCondition();
object flag = EvalExpress(s);
System.Console.WriteLine(flag.ToString());
System.Console.ReadLine();
}

}
}